diff --git a/.github/schemas/signals.schema.json b/.github/schemas/signals.schema.json
index 1130cf22..ded4367e 100644
--- a/.github/schemas/signals.schema.json
+++ b/.github/schemas/signals.schema.json
@@ -1,14 +1,13 @@
 {
   "$schema": "https://json-schema.org/draft/2020-12/schema",
   "$id": "https://github.com/petry-projects/.github/blob/main/.github/schemas/signals.schema.json",
-  "$comment": "version: 1.1.0 — must match SCHEMA_VERSION in collect-signals.sh; enforced by bats",
+  "$comment": "version: 1.0.0 — must match SCHEMA_VERSION in collect-signals.sh; enforced by bats",
   "title": "Feature Ideation Signals",
   "description": "Canonical contract between collect-signals.sh and the BMAD Analyst (Mary) prompt. Any change to this schema is a breaking change to the workflow.",
   "type": "object",
   "required": [
     "schema_version",
     "scan_date",
-    "last_successful_run",
     "repo",
     "open_issues",
     "closed_issues_30d",
@@ -29,11 +28,6 @@
       "type": "string",
       "format": "date-time"
     },
-    "last_successful_run": {
-      "description": "ISO-8601 timestamp of the previous successful workflow run; used as a feed checkpoint by the analyst to skip already-reviewed content.",
-      "type": "string",
-      "format": "date-time"
-    },
     "repo": {
       "type": "string",
       "pattern": "^[^/]+/[^/]+$"
diff --git a/.github/scripts/feature-ideation/README.md b/.github/scripts/feature-ideation/README.md
index 372125c3..f213172e 100644
--- a/.github/scripts/feature-ideation/README.md
+++ b/.github/scripts/feature-ideation/README.md
@@ -51,7 +51,7 @@ bats test/workflows/feature-ideation/gh-safe.bats
   shellcheck -x collect-signals.sh lint-prompt.sh match-discussions.sh \
                  discussion-mutations.sh lib/*.sh)
 
-# Lint the workflow's direct_prompt block
+# Lint workflow prompt blocks (direct_prompt: and prompt:)
 bash .github/scripts/feature-ideation/lint-prompt.sh
 ```
 
@@ -76,7 +76,7 @@ signals.json is a breaking change and must:
 
 1. Bump `SCHEMA_VERSION` in `collect-signals.sh`.
 2. Update fixtures under `test/workflows/feature-ideation/fixtures/expected/`.
-3. Update Mary's prompt in `feature-ideation.yml` if any field references move.
+3. Update Mary's prompt in `.github/workflows/feature-ideation-reusable.yml` if any field references move.
 
 CI validates every fixture against the schema, and the workflow validates
 the runtime output before handing it to Mary.
diff --git a/.github/scripts/feature-ideation/collect-signals.sh b/.github/scripts/feature-ideation/collect-signals.sh
index 0a11f77f..b2ae23cc 100755
--- a/.github/scripts/feature-ideation/collect-signals.sh
+++ b/.github/scripts/feature-ideation/collect-signals.sh
@@ -31,7 +31,7 @@ set -euo pipefail
 # if the constants drift, AND the bats `signals-schema: SCHEMA_VERSION
 # constant matches schema file` test enforces this in CI.
 # Caught by CodeRabbit review on PR petry-projects/.github#85.
-SCHEMA_VERSION="1.1.0"
+SCHEMA_VERSION="1.0.0"
 
 SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
 # shellcheck source=lib/gh-safe.sh
@@ -58,56 +58,39 @@ main() {
   local discussion_limit="${DISCUSSION_LIMIT:-100}"
   local output_path="${SIGNALS_OUTPUT:-./signals.json}"
 
-  local owner repo_name
-  owner="${REPO%%/*}"
-  repo_name="${REPO##*/}"
-  if [ "$owner" = "$REPO" ] || [ -z "$repo_name" ]; then
+  # Validate that limit overrides are positive integers before forwarding to
+  # GraphQL — a value like `ISSUE_LIMIT=foo` would cause an opaque downstream
+  # failure instead of a clean usage error. Caught by CodeRabbit review on
+  # PR petry-projects/.github#85.
+  local _lim_name _lim_val
+  for _lim_name in ISSUE_LIMIT PR_LIMIT DISCUSSION_LIMIT; do
+    case "$_lim_name" in
+      ISSUE_LIMIT)      _lim_val="$issue_limit" ;;
+      PR_LIMIT)         _lim_val="$pr_limit" ;;
+      DISCUSSION_LIMIT) _lim_val="$discussion_limit" ;;
+    esac
+    if [[ ! $_lim_val =~ ^[1-9][0-9]*$ ]]; then
+      printf '[collect-signals] %s must be a positive integer, got: %s\n' "$_lim_name" "$_lim_val" >&2
+      return 64
+    fi
+  done
+
+  # Strict owner/name format — reject leading/trailing slashes, empty segments,
+  # and extra path parts (e.g. "org//repo", "/repo", "org/repo/extra").
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  if [[ ! $REPO =~ ^[^/]+/[^/]+$ ]]; then
     printf '[collect-signals] REPO must be in owner/name format, got: %s\n' "$REPO" >&2
     return 64
   fi
+  local owner repo_name
+  owner="${REPO%%/*}"
+  repo_name="${REPO##*/}"
 
   local thirty_days_ago
   thirty_days_ago=$(date_days_ago 30)
   local scan_date
   scan_date=$(date_now_iso)
 
-  # --- Feed checkpoint: last successful run ----------------------------------
-  # Used by the analyst to skip feed entries already reviewed. The current run
-  # is still in-progress, so --status=success --limit=1 reliably returns the
-  # previous successful run. Falls back to 30 days ago on first-ever run or
-  # after a long gap so the initial scan is bounded.
-  # WORKFLOW_FILE — caller-supplied env var for repos that name their stub
-  # something other than the conventional "feature-ideation.yml". Defaults to
-  # the conventional name; no change needed for repos that follow the standard.
-  printf '[collect-signals] resolving feed checkpoint (last successful run)\n' >&2
-  local last_successful_run _run_stderr _run_err
-  _run_stderr=$(mktemp)
-  last_successful_run=$(gh run list \
-    --repo "$REPO" \
-    --workflow="${WORKFLOW_FILE:-feature-ideation.yml}" \
-    --status=success \
-    --limit=1 \
-    --json createdAt \
-    --jq '.[0].createdAt // empty' \
-    2>"$_run_stderr" || true)
-  _run_err=$(cat "$_run_stderr")
-  rm -f "$_run_stderr"
-  # Validate that the result looks like an ISO-8601 datetime. The real `gh`
-  # CLI applies the --jq filter and emits a bare timestamp; in test environments
-  # the gh stub returns raw fixture JSON (without applying --jq), so we guard
-  # against that here rather than requiring every test to stub this extra call.
-  if [ -z "$last_successful_run" ] || [ "$last_successful_run" = "null" ] || \
-     ! printf '%s' "$last_successful_run" | grep -qE '^[0-9]{4}-[0-9]{2}-[0-9]{2}T'; then
-    if [ -n "$_run_err" ]; then
-      printf '[collect-signals] gh run list warning: %s\n' "$_run_err" >&2
-    fi
-    last_successful_run="$(date_days_ago 30)T00:00:00Z"
-    printf '[collect-signals] no prior successful run found; using 30-day fallback: %s\n' \
-      "$last_successful_run" >&2
-  else
-    printf '[collect-signals] feed checkpoint: %s\n' "$last_successful_run" >&2
-  fi
-
   local truncation_warnings='[]'
 
   # --- Open issues -----------------------------------------------------------
@@ -238,7 +221,6 @@ GRAPHQL
     "$bug_reports" \
     "$REPO" \
     "$scan_date" \
-    "$last_successful_run" \
     "$SCHEMA_VERSION" \
     "$truncation_warnings")
 
@@ -255,7 +237,6 @@ GRAPHQL
       printf -- '- **Bug reports:** %s\n' "$(jq '.bug_reports.count' "$output_path")"
       printf -- '- **Merged PRs (30d):** %s\n' "$(jq '.merged_prs_30d.count' "$output_path")"
       printf -- '- **Existing Ideas discussions:** %s\n' "$(jq '.ideas_discussions.count' "$output_path")"
-      printf -- '- **Feed checkpoint (last successful run):** %s\n' "$(jq -r '.last_successful_run' "$output_path")"
       local warn_count
       warn_count=$(jq '.truncation_warnings | length' "$output_path")
       if [ "$warn_count" -gt 0 ]; then
diff --git a/.github/scripts/feature-ideation/lib/compose-signals.sh b/.github/scripts/feature-ideation/lib/compose-signals.sh
index 1afd8e7b..1c699349 100755
--- a/.github/scripts/feature-ideation/lib/compose-signals.sh
+++ b/.github/scripts/feature-ideation/lib/compose-signals.sh
@@ -18,17 +18,16 @@
 #   $7  bug_reports
 #   $8  repo (string, e.g. "petry-projects/talkterm")
 #   $9  scan_date (ISO-8601 string)
-#  $10  last_successful_run (ISO-8601 string; feed checkpoint)
-#  $11  schema_version (string)
-#  $12  truncation_warnings (JSON array, may be [])
+#  $10  schema_version (string)
+#  $11  truncation_warnings (JSON array, may be [])
 #
 # Output: signals.json document on stdout.
 
 set -euo pipefail
 
 compose_signals() {
-  if [ "$#" -ne 12 ]; then
-    printf '[compose-signals] expected 12 args, got %d\n' "$#" >&2
+  if [ "$#" -ne 11 ]; then
+    printf '[compose-signals] expected 11 args, got %d\n' "$#" >&2
     return 64  # EX_USAGE
   fi
 
@@ -41,9 +40,8 @@ compose_signals() {
   local bug_reports="$7"
   local repo="$8"
   local scan_date="$9"
-  local last_successful_run="${10}"
-  local schema_version="${11}"
-  local truncation_warnings="${12}"
+  local schema_version="${10}"
+  local truncation_warnings="${11}"
 
   # Validate every JSON input before composition. Better to fail loudly here
   # than to let `jq --argjson` produce a cryptic parse error.
@@ -51,15 +49,17 @@ compose_signals() {
   for input in "$open_issues" "$closed_issues" "$ideas_discussions" "$releases" \
                "$merged_prs" "$feature_requests" "$bug_reports" "$truncation_warnings"; do
     idx=$((idx + 1))
-    if ! printf '%s' "$input" | jq -e . >/dev/null 2>&1; then
-      printf '[compose-signals] arg #%d is not valid JSON: %s\n' "$idx" "${input:0:120}" >&2
+    # Require a JSON array, not just valid JSON. Objects/strings/nulls accepted
+    # by `jq -e .` would silently produce wrong counts (key count, char count).
+    # Caught by CodeRabbit review on PR petry-projects/.github#85.
+    if ! printf '%s' "$input" | jq -e 'type == "array"' >/dev/null 2>&1; then
+      printf '[compose-signals] arg #%d must be a JSON array: %s\n' "$idx" "${input:0:120}" >&2
       return 65  # EX_DATAERR
     fi
   done
 
   jq -n \
     --arg scan_date "$scan_date" \
-    --arg last_successful_run "$last_successful_run" \
     --arg repo "$repo" \
     --arg schema_version "$schema_version" \
     --argjson open_issues "$open_issues" \
@@ -73,7 +73,6 @@ compose_signals() {
     '{
       schema_version: $schema_version,
       scan_date: $scan_date,
-      last_successful_run: $last_successful_run,
       repo: $repo,
       open_issues: { count: ($open_issues | length), items: $open_issues },
       closed_issues_30d: { count: ($closed_issues | length), items: $closed_issues },
diff --git a/.github/scripts/feature-ideation/lib/date-utils.sh b/.github/scripts/feature-ideation/lib/date-utils.sh
index 8c4b5a12..ae2722bd 100755
--- a/.github/scripts/feature-ideation/lib/date-utils.sh
+++ b/.github/scripts/feature-ideation/lib/date-utils.sh
@@ -10,6 +10,13 @@ set -euo pipefail
 
 # Print an ISO date (YYYY-MM-DD) for N days ago in UTC.
 date_days_ago() {
+  # Guard arg count before reading $1: under set -u a zero-arg call would abort
+  # the shell with "unbound variable" instead of reaching the validation path.
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  if [ "$#" -ne 1 ]; then
+    printf '[date-utils] expected 1 arg (days), got: %d\n' "$#" >&2
+    return 64
+  fi
   local days="$1"
   if [ -z "$days" ] || ! printf '%s' "$days" | grep -Eq '^[0-9]+$'; then
     printf '[date-utils] days must be a non-negative integer, got: %s\n' "$days" >&2
diff --git a/.github/scripts/feature-ideation/lib/filter-bots.sh b/.github/scripts/feature-ideation/lib/filter-bots.sh
index f2fbfdec..f994e3e2 100755
--- a/.github/scripts/feature-ideation/lib/filter-bots.sh
+++ b/.github/scripts/feature-ideation/lib/filter-bots.sh
@@ -35,9 +35,11 @@ DEFAULT_BOT_AUTHORS=(
 filter_bots_build_list() {
   local list=("${DEFAULT_BOT_AUTHORS[@]}")
   if [ -n "${FEATURE_IDEATION_BOT_AUTHORS:-}" ]; then
-    local IFS=','
-    # shellcheck disable=SC2206
-    local extras=($FEATURE_IDEATION_BOT_AUTHORS)
+    # Use `IFS=',' read` (not unquoted expansion) to avoid pathname-globbing
+    # against the filesystem if any entry contains wildcard characters.
+    # Caught by CodeRabbit review on PR petry-projects/.github#85.
+    local extras=()
+    IFS=',' read -r -a extras <<<"${FEATURE_IDEATION_BOT_AUTHORS}"
     # Trim leading/trailing whitespace from each comma-separated entry so
     # `"bot1, bot2"` resolves to `bot1` and `bot2`, not `bot1` and ` bot2`.
     # Caught by CodeRabbit review on PR petry-projects/.github#85.
diff --git a/.github/scripts/feature-ideation/lib/gh-safe.sh b/.github/scripts/feature-ideation/lib/gh-safe.sh
index 343a5bbc..8060c5c4 100755
--- a/.github/scripts/feature-ideation/lib/gh-safe.sh
+++ b/.github/scripts/feature-ideation/lib/gh-safe.sh
@@ -93,6 +93,13 @@ gh_safe_graphql() {
   local i=0
   while [ "$i" -lt "${#args[@]}" ]; do
     if [ "${args[$i]}" = "--jq" ]; then
+      # Guard bounds before dereferencing args[i+1]: under set -u an out-of-
+      # bounds access aborts the shell. Caught by CodeRabbit review on PR
+      # petry-projects/.github#85.
+      if [ $((i + 1)) -ge "${#args[@]}" ]; then
+        _gh_safe_err "graphql-bad-args" "--jq requires a jq filter argument"
+        return 64
+      fi
       has_jq=1
       jq_filter="${args[$((i + 1))]}"
       break
@@ -132,13 +139,11 @@ gh_safe_graphql() {
   fi
 
   # Reject error envelopes — GraphQL returns 200 OK even on partial errors.
-  if printf '%s' "$raw" | jq -e '.errors // empty | if . then true else false end' >/dev/null 2>&1; then
-    if printf '%s' "$raw" | jq -e '(.errors | type) == "array" and (.errors | length > 0)' >/dev/null 2>&1; then
-      local errs
-      errs=$(printf '%s' "$raw" | jq -c '.errors')
-      _gh_safe_err "graphql-errors" "$errs"
-      return 66  # EX_NOINPUT — repurposed: "GraphQL refused our request"
-    fi
+  if printf '%s' "$raw" | jq -e '(.errors // empty | type) == "array" and (.errors | length > 0)' >/dev/null 2>&1; then
+    local errs
+    errs=$(printf '%s' "$raw" | jq -c '.errors')
+    _gh_safe_err "graphql-errors" "$errs"
+    return 66  # EX_NOINPUT — repurposed: "GraphQL refused our request"
   fi
 
   # Reject `data: null` — usually means the path didn't resolve (permissions,
@@ -187,6 +192,13 @@ gh_safe_graphql() {
 # Same defensive contract as `gh_safe_graphql`: any auth/network/schema
 # failure exits non-zero with a structured stderr message.
 gh_safe_graphql_input() {
+  # Guard arg count before reading $1: under set -u a zero-arg call aborts the
+  # shell instead of reaching the JSON validation. Caught by CodeRabbit review
+  # on PR petry-projects/.github#85.
+  if [ "$#" -ne 1 ]; then
+    _gh_safe_err "graphql-bad-input" "expected 1 arg: JSON request body, got $#"
+    return 64
+  fi
   local body="$1"
   if ! gh_safe_is_json "$body"; then
     _gh_safe_err "graphql-bad-input" "request body is not valid JSON"
diff --git a/.github/scripts/feature-ideation/lint-prompt.sh b/.github/scripts/feature-ideation/lint-prompt.sh
index ad8226de..a1d18b63 100755
--- a/.github/scripts/feature-ideation/lint-prompt.sh
+++ b/.github/scripts/feature-ideation/lint-prompt.sh
@@ -31,6 +31,34 @@ scan_file() {
 import re
 import sys
 
+
+def _strip_github_expressions(s: str) -> str:
+    """Remove ${{ ... }} GitHub Actions expressions from s.
+
+    Uses a stateful scanner instead of `[^}]*` regex so that expressions
+    containing `}` inside string literals (e.g. format() calls) are fully
+    consumed rather than prematurely terminated. This prevents false-positive
+    shell-expansion matches on content that is actually inside a GH expression.
+    Caught by CodeRabbit review on PR petry-projects/.github#85.
+    """
+    result: list[str] = []
+    i = 0
+    while i < len(s):
+        if s[i : i + 3] == "${{":
+            # Consume until we find the matching "}}"
+            j = i + 3
+            while j < len(s):
+                if s[j : j + 2] == "}}":
+                    j += 2
+                    break
+                j += 1
+            i = j  # skip the whole ${{ ... }} expression
+        else:
+            result.append(s[i])
+            i += 1
+    return "".join(result)
+
+
 path = sys.argv[1]
 try:
     with open(path, "r", encoding="utf-8") as f:
@@ -55,8 +83,10 @@ findings = []
 shell_expansion = re.compile(r'(?<![\\$])\$\([^)]*\)|(?<![\\$])\$\{[A-Za-z_][A-Za-z0-9_]*\}')
 
 # Recognise both `direct_prompt:` (v0) and `prompt:` (v1) markers, with
-# optional `|` or `>` block scalar indicators.
-prompt_marker = re.compile(r'(?:direct_prompt|prompt):\s*[|>]?\s*$')
+# optional `|` or `>` block scalar indicators plus YAML chomping modifiers
+# (`-` or `+`) so `prompt: |-`, `prompt: |+`, `prompt: >-`, `prompt: >+`
+# are all recognised. Caught by CodeRabbit review on PR petry-projects/.github#85.
+prompt_marker = re.compile(r'(?:direct_prompt|prompt):\s*[|>]?[-+]?\s*$')
 
 for lineno, raw in enumerate(lines, start=1):
     stripped = raw.lstrip(" ")
@@ -78,8 +108,13 @@ for lineno, raw in enumerate(lines, start=1):
             continue
 
         # We're inside the prompt body. Scan for shell expansions.
-        # First, strip out any GitHub Actions expressions so they don't trip us.
-        no_gh = re.sub(r'\$\{\{[^}]*\}\}', '', raw)
+        # First, strip out GitHub Actions ${{ ... }} expressions.
+        # The naive `[^}]*` regex stops at the first `}`, so expressions that
+        # contain `}` internally (e.g. format() calls or string literals) are
+        # not fully removed and leave false-positive shell expansion matches.
+        # Use a small stateful scanner instead.
+        # Caught by CodeRabbit review on PR petry-projects/.github#85.
+        no_gh = _strip_github_expressions(raw)
         for match in shell_expansion.finditer(no_gh):
             findings.append((lineno, match.group(0), raw.rstrip()))
 
@@ -107,15 +142,27 @@ main() {
   fi
 
   local exit=0
+  local file_rc=0
   for file in "$@"; do
     if [ ! -f "$file" ]; then
       printf '[lint-prompt] not found: %s\n' "$file" >&2
       exit=2
       continue
     fi
-    if ! scan_file "$file"; then
-      exit=1
+    # Capture the actual exit code so we preserve exit-2 (file error) over
+    # exit-1 (lint finding). A later lint failure must not overwrite an earlier
+    # file error. Caught by CodeRabbit review on PR petry-projects/.github#85.
+    if scan_file "$file"; then
+      file_rc=0
+    else
+      file_rc=$?
     fi
+    case "$file_rc" in
+      0) ;;
+      1) if [ "$exit" -eq 0 ]; then exit=1; fi ;;
+      2) exit=2 ;;
+      *) return "$file_rc" ;;
+    esac
   done
   return "$exit"
 }
diff --git a/.github/scripts/feature-ideation/match-discussions.sh b/.github/scripts/feature-ideation/match-discussions.sh
index d8bf7668..c4af5466 100755
--- a/.github/scripts/feature-ideation/match-discussions.sh
+++ b/.github/scripts/feature-ideation/match-discussions.sh
@@ -97,49 +97,91 @@ def jaccard(a: set[str], b: set[str]) -> float:
     return len(a & b) / len(a | b)
 
 
-with open(signals_path) as f:
-    signals = json.load(f)
-with open(proposals_path) as f:
-    proposals = json.load(f)
+def _load_json(path: str, label: str):
+    """Load JSON from path, exiting with code 2 on any read or parse error."""
+    try:
+        with open(path, encoding="utf-8") as f:
+            return json.load(f)
+    except OSError as exc:
+        sys.stderr.write(f"[match-discussions] cannot read {label}: {exc}\n")
+        sys.exit(2)
+    except json.JSONDecodeError as exc:
+        sys.stderr.write(f"[match-discussions] invalid JSON in {label}: {exc}\n")
+        sys.exit(2)
+
+
+signals = _load_json(signals_path, "signals")
+proposals = _load_json(proposals_path, "proposals")
 
 if not isinstance(proposals, list):
     sys.stderr.write("[match-discussions] proposals must be a JSON array\n")
     sys.exit(65)
 
 discussions = signals.get("ideas_discussions", {}).get("items", []) or []
-disc_norm = [(d, normalize(d.get("title", ""))) for d in discussions]
-
-matched = []
-new_candidates = []
-seen_disc_ids = set()
-
-for proposal in proposals:
+# Skip discussions without an id to avoid all id-less entries collapsing into
+# a single `None` key in seen_disc_ids. Caught by CodeRabbit on PR #85.
+disc_norm = [
+    (d, normalize(d.get("title", "")))
+    for d in discussions
+    if d.get("id") is not None
+]
+
+# --- Optimal (similarity-sorted) matching ------------------------------------
+# The original greedy per-proposal loop consumed discussions in proposal order,
+# so an early lower-value match could block a later higher-value match.
+# Instead we enumerate all (proposal, discussion) pairs, sort by similarity
+# descending (ties broken by original proposal index for stability), then
+# assign greedily. This guarantees globally higher-value matches are honoured
+# first. Caught by CodeRabbit review on PR petry-projects/.github#85.
+
+# Collect valid proposals with their original index (for tie-breaking + new_candidates).
+proposals_indexed: list[tuple[int, dict]] = []
+for p_idx, proposal in enumerate(proposals):
     if not isinstance(proposal, dict) or "title" not in proposal:
         sys.stderr.write(f"[match-discussions] skipping malformed proposal: {proposal!r}\n")
         continue
-    p_norm = normalize(proposal["title"])
+    proposals_indexed.append((p_idx, proposal))
 
-    best = None
-    best_sim = 0.0
+# Build all (similarity, proposal_idx, disc_id, proposal, disc) tuples.
+all_pairs: list[tuple[float, int, str, dict, dict]] = []
+for p_idx, proposal in proposals_indexed:
+    p_norm = normalize(proposal["title"])
     for disc, d_norm in disc_norm:
-        if disc.get("id") in seen_disc_ids:
-            continue
         sim = jaccard(p_norm, d_norm)
-        if sim > best_sim:
-            best_sim = sim
-            best = disc
+        all_pairs.append((sim, p_idx, disc["id"], proposal, disc))
 
-    if best is not None and best_sim >= threshold:
+# Sort descending by similarity; stable tie-break by proposal index ascending.
+all_pairs.sort(key=lambda x: (-x[0], x[1]))
+
+matched = []
+seen_disc_ids: set[str] = set()
+seen_proposal_idxs: set[int] = set()
+
+for sim, p_idx, disc_id, proposal, disc in all_pairs:
+    if p_idx in seen_proposal_idxs or disc_id in seen_disc_ids:
+        continue
+    if sim >= threshold:
         matched.append(
             {
                 "proposal": proposal,
-                "discussion": best,
-                "similarity": round(best_sim, 4),
+                "discussion": disc,
+                "similarity": round(sim, 4),
             }
         )
-        seen_disc_ids.add(best.get("id"))
-    else:
-        new_candidates.append({"proposal": proposal, "best_similarity": round(best_sim, 4)})
+        seen_disc_ids.add(disc_id)
+        seen_proposal_idxs.add(p_idx)
+
+# Unmatched proposals become new candidates.
+new_candidates = []
+for p_idx, proposal in proposals_indexed:
+    if p_idx in seen_proposal_idxs:
+        continue
+    p_norm = normalize(proposal["title"])
+    best_sim = max(
+        (jaccard(p_norm, d_norm) for _, d_norm in disc_norm),
+        default=0.0,
+    )
+    new_candidates.append({"proposal": proposal, "best_similarity": round(best_sim, 4)})
 
 result = {
     "matched": matched,
diff --git a/.github/scripts/feature-ideation/validate-signals.py b/.github/scripts/feature-ideation/validate-signals.py
index eb82ff7c..e163cf62 100755
--- a/.github/scripts/feature-ideation/validate-signals.py
+++ b/.github/scripts/feature-ideation/validate-signals.py
@@ -53,7 +53,12 @@ def main(argv: list[str]) -> int:
         return 2
 
     try:
-        signals = json.loads(signals_path.read_text())
+        signals = json.loads(signals_path.read_text(encoding="utf-8"))
+    except OSError as exc:
+        # File read errors (permissions, I/O) must also exit 2. Caught by
+        # CodeRabbit review on PR petry-projects/.github#85.
+        sys.stderr.write(f"[validate-signals] cannot read {signals_path}: {exc}\n")
+        return 2
     except json.JSONDecodeError as exc:
         # Per the docstring contract, exit 2 means usage / file error and
         # exit 1 means schema validation error. A malformed signals file
@@ -63,7 +68,10 @@ def main(argv: list[str]) -> int:
         return 2
 
     try:
-        schema = json.loads(schema_path.read_text())
+        schema = json.loads(schema_path.read_text(encoding="utf-8"))
+    except OSError as exc:
+        sys.stderr.write(f"[validate-signals] cannot read schema {schema_path}: {exc}\n")
+        return 2
     except json.JSONDecodeError as exc:
         sys.stderr.write(f"[validate-signals] invalid schema JSON: {exc}\n")
         return 2
@@ -79,7 +87,7 @@ def main(argv: list[str]) -> int:
     format_checker = FormatChecker()
 
     @format_checker.checks("date-time", raises=(ValueError, TypeError))
-    def _check_date_time(instance):  # noqa: ANN001 — jsonschema callback signature
+    def _check_date_time(instance) -> bool:  # noqa: ANN001 — jsonschema callback signature
         if not isinstance(instance, str):
             return True  # non-strings handled by `type` keyword, not format
         # Must look like a date-time, not just any string. Require at least
diff --git a/.github/workflows/feature-ideation-tests.yml b/.github/workflows/feature-ideation-tests.yml
index 589c9349..91c1a628 100644
--- a/.github/workflows/feature-ideation-tests.yml
+++ b/.github/workflows/feature-ideation-tests.yml
@@ -103,7 +103,7 @@ jobs:
 
       - name: Upload bats output on failure
         if: failure()
-        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: bats-output
           path: |
diff --git a/test/workflows/feature-ideation/collect-signals.bats b/test/workflows/feature-ideation/collect-signals.bats
index cf306ff2..94f9a12b 100644
--- a/test/workflows/feature-ideation/collect-signals.bats
+++ b/test/workflows/feature-ideation/collect-signals.bats
@@ -21,17 +21,15 @@ teardown() {
 
 # Build a multi-call gh script for the standard happy path.
 # Order MUST match collect-signals.sh:
-#   1. gh run list (feed checkpoint — last successful run)
-#   2. gh issue list --state open
-#   3. gh issue list --state closed
-#   4. gh api graphql (categories)
-#   5. gh api graphql (discussions)
-#   6. gh release list
-#   7. gh pr list --state merged
+#   1. gh issue list --state open
+#   2. gh issue list --state closed
+#   3. gh api graphql (categories)
+#   4. gh api graphql (discussions)
+#   5. gh release list
+#   6. gh pr list --state merged
 build_happy_script() {
   local script="${TT_TMP}/gh-script.tsv"
   : >"$script"
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-open.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-closed.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/graphql-categories.json" >>"$script"
@@ -117,9 +115,7 @@ build_happy_script() {
   script="${TT_TMP}/gh-script.tsv"
   err_file="${TT_TMP}/auth-err.txt"
   printf 'HTTP 401: Bad credentials\n' >"$err_file"
-  # run list (feed checkpoint — silenced with || true, so failure falls back)
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >"$script"
-  printf '4\t-\t%s\n' "$err_file" >>"$script"
+  printf '4\t-\t%s\n' "$err_file" >"$script"
   export GH_STUB_SCRIPT="$script"
   rm -f "${TT_TMP}/.gh-stub-counter"
 
@@ -131,7 +127,6 @@ build_happy_script() {
 @test "collect-signals: FAILS LOUD on GraphQL errors envelope (categories)" {
   script="${TT_TMP}/gh-script.tsv"
   : >"$script"
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-open.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-closed.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/graphql-errors-envelope.json" >>"$script"
@@ -188,7 +183,6 @@ JSON
 
   script="${TT_TMP}/gh-script.tsv"
   : >"$script"
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >>"$script"  # feed checkpoint
   printf '0\t%s\t-\n' "$bot_file"   >>"$script"   # open issues — all bots
   printf '0\t%s\t-\n' "$empty_file" >>"$script"   # closed issues
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/graphql-no-ideas-category.json" >>"$script"
@@ -208,7 +202,6 @@ JSON
 @test "collect-signals: emits truncation warning when discussions hasNextPage=true" {
   script="${TT_TMP}/gh-script.tsv"
   : >"$script"
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-open.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-closed.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/graphql-categories.json" >>"$script"
@@ -232,7 +225,6 @@ JSON
 @test "collect-signals: skips discussions when Ideas category absent" {
   script="${TT_TMP}/gh-script.tsv"
   : >"$script"
-  printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/run-list-last-success.txt" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-open.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/issue-list-closed.json" >>"$script"
   printf '0\t%s\t-\n' "${TT_FIXTURES_DIR}/gh-responses/graphql-no-ideas-category.json" >>"$script"
diff --git a/test/workflows/feature-ideation/compose-signals.bats b/test/workflows/feature-ideation/compose-signals.bats
index 35359e90..4dced2c8 100644
--- a/test/workflows/feature-ideation/compose-signals.bats
+++ b/test/workflows/feature-ideation/compose-signals.bats
@@ -18,7 +18,6 @@ compose_empty() {
     '[]' '[]' '[]' '[]' '[]' '[]' '[]' \
     'foo/bar' \
     '2026-04-07T00:00:00Z' \
-    '2026-03-07T00:00:00Z' \
     '1.0.0' \
     '[]'
 }
@@ -35,14 +34,14 @@ compose_empty() {
 @test "compose: rejects empty string for any JSON arg" {
   run compose_signals \
     '' '[]' '[]' '[]' '[]' '[]' '[]' \
-    'foo/bar' '2026-04-07T00:00:00Z' '2026-03-07T00:00:00Z' '1.0.0' '[]'
+    'foo/bar' '2026-04-07T00:00:00Z' '1.0.0' '[]'
   [ "$status" -ne 0 ]
 }
 
 @test "compose: rejects non-JSON for any JSON arg" {
   run compose_signals \
     'not json' '[]' '[]' '[]' '[]' '[]' '[]' \
-    'foo/bar' '2026-04-07T00:00:00Z' '2026-03-07T00:00:00Z' '1.0.0' '[]'
+    'foo/bar' '2026-04-07T00:00:00Z' '1.0.0' '[]'
   [ "$status" -ne 0 ]
 }
 
@@ -53,9 +52,9 @@ compose_empty() {
 @test "compose: produces all required top-level fields with empty inputs" {
   run compose_empty
   [ "$status" -eq 0 ]
-  for field in schema_version scan_date last_successful_run repo open_issues \
-               closed_issues_30d ideas_discussions releases merged_prs_30d \
-               feature_requests bug_reports truncation_warnings; do
+  for field in schema_version scan_date repo open_issues closed_issues_30d \
+               ideas_discussions releases merged_prs_30d feature_requests \
+               bug_reports truncation_warnings; do
     printf '%s' "$output" | jq -e "has(\"$field\")" >/dev/null
   done
 }
@@ -64,7 +63,7 @@ compose_empty() {
   open='[{"number":1,"title":"a","labels":[]},{"number":2,"title":"b","labels":[]}]'
   run compose_signals \
     "$open" '[]' '[]' '[]' '[]' '[]' '[]' \
-    'foo/bar' '2026-04-07T00:00:00Z' '2026-03-07T00:00:00Z' '1.0.0' '[]'
+    'foo/bar' '2026-04-07T00:00:00Z' '1.0.0' '[]'
   [ "$status" -eq 0 ]
   count=$(printf '%s' "$output" | jq '.open_issues.count')
   items_len=$(printf '%s' "$output" | jq '.open_issues.items | length')
@@ -75,7 +74,7 @@ compose_empty() {
 @test "compose: schema_version is preserved verbatim" {
   run compose_signals \
     '[]' '[]' '[]' '[]' '[]' '[]' '[]' \
-    'foo/bar' '2026-04-07T00:00:00Z' '2026-03-07T00:00:00Z' '2.5.1' '[]'
+    'foo/bar' '2026-04-07T00:00:00Z' '2.5.1' '[]'
   [ "$status" -eq 0 ]
   v=$(printf '%s' "$output" | jq -r '.schema_version')
   [ "$v" = "2.5.1" ]
@@ -85,7 +84,7 @@ compose_empty() {
   warnings='[{"source":"open_issues","limit":50,"message":"truncated"}]'
   run compose_signals \
     '[]' '[]' '[]' '[]' '[]' '[]' '[]' \
-    'foo/bar' '2026-04-07T00:00:00Z' '2026-03-07T00:00:00Z' '1.0.0' "$warnings"
+    'foo/bar' '2026-04-07T00:00:00Z' '1.0.0' "$warnings"
   [ "$status" -eq 0 ]
   src=$(printf '%s' "$output" | jq -r '.truncation_warnings[0].source')
   [ "$src" = "open_issues" ]
@@ -94,7 +93,7 @@ compose_empty() {
 @test "compose: scan_date and repo round-trip exactly" {
   run compose_signals \
     '[]' '[]' '[]' '[]' '[]' '[]' '[]' \
-    'octocat/hello-world' '2030-01-15T12:34:56Z' '2029-12-15T12:34:56Z' '1.0.0' '[]'
+    'octocat/hello-world' '2030-01-15T12:34:56Z' '1.0.0' '[]'
   [ "$status" -eq 0 ]
   d=$(printf '%s' "$output" | jq -r '.scan_date')
   r=$(printf '%s' "$output" | jq -r '.repo')
diff --git a/test/workflows/feature-ideation/date-utils.bats b/test/workflows/feature-ideation/date-utils.bats
index dfb132b2..a26749ff 100644
--- a/test/workflows/feature-ideation/date-utils.bats
+++ b/test/workflows/feature-ideation/date-utils.bats
@@ -15,7 +15,10 @@ setup() {
 }
 
 @test "date_days_ago: 0 returns today" {
-  today=$(date -u +%Y-%m-%d)
+  # Use the helper function rather than the raw system `date` call so the test
+  # validates behaviour consistently on both GNU and BSD systems.
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  today=$(date_today)
   run date_days_ago 0
   [ "$status" -eq 0 ]
   [ "$output" = "$today" ]
diff --git a/test/workflows/feature-ideation/fixtures/expected/empty-repo.signals.json b/test/workflows/feature-ideation/fixtures/expected/empty-repo.signals.json
index e6438b55..4101afb6 100644
--- a/test/workflows/feature-ideation/fixtures/expected/empty-repo.signals.json
+++ b/test/workflows/feature-ideation/fixtures/expected/empty-repo.signals.json
@@ -1,7 +1,6 @@
 {
-  "schema_version": "1.1.0",
+  "schema_version": "1.0.0",
   "scan_date": "2026-04-07T07:00:00Z",
-  "last_successful_run": "2026-03-31T07:00:00Z",
   "repo": "petry-projects/talkterm",
   "open_issues": { "count": 0, "items": [] },
   "closed_issues_30d": { "count": 0, "items": [] },
diff --git a/test/workflows/feature-ideation/fixtures/expected/populated.signals.json b/test/workflows/feature-ideation/fixtures/expected/populated.signals.json
index 5618e36d..4c929219 100644
--- a/test/workflows/feature-ideation/fixtures/expected/populated.signals.json
+++ b/test/workflows/feature-ideation/fixtures/expected/populated.signals.json
@@ -1,7 +1,6 @@
 {
-  "schema_version": "1.1.0",
+  "schema_version": "1.0.0",
   "scan_date": "2026-04-07T07:00:00Z",
-  "last_successful_run": "2026-03-31T07:00:00Z",
   "repo": "petry-projects/talkterm",
   "open_issues": {
     "count": 2,
diff --git a/test/workflows/feature-ideation/fixtures/expected/truncated.signals.json b/test/workflows/feature-ideation/fixtures/expected/truncated.signals.json
index 2c884ea6..845db66f 100644
--- a/test/workflows/feature-ideation/fixtures/expected/truncated.signals.json
+++ b/test/workflows/feature-ideation/fixtures/expected/truncated.signals.json
@@ -1,7 +1,6 @@
 {
-  "schema_version": "1.1.0",
+  "schema_version": "1.0.0",
   "scan_date": "2026-04-07T07:00:00Z",
-  "last_successful_run": "2026-03-31T07:00:00Z",
   "repo": "petry-projects/talkterm",
   "open_issues": { "count": 0, "items": [] },
   "closed_issues_30d": { "count": 0, "items": [] },
diff --git a/test/workflows/feature-ideation/gh-safe.bats b/test/workflows/feature-ideation/gh-safe.bats
index b06bb5c7..046446d7 100644
--- a/test/workflows/feature-ideation/gh-safe.bats
+++ b/test/workflows/feature-ideation/gh-safe.bats
@@ -222,3 +222,14 @@ teardown() {
     run gh_safe_graphql_input '{"query":"q","variables":{}}'
   [ "$status" -ne 0 ]
 }
+
+# ---------------------------------------------------------------------------
+# gh stub — self-tests for stub defensive behaviour
+# ---------------------------------------------------------------------------
+
+@test "gh stub: fails fast when GH_STUB_SCRIPT is set but file is missing" {
+  GH_STUB_SCRIPT="/nonexistent/path/script.sh" \
+    run --separate-stderr "${TT_TMP}/bin/gh" issue list
+  [ "$status" -ne 0 ]
+  [[ "$stderr" == *"not found"* ]]
+}
diff --git a/test/workflows/feature-ideation/lint-prompt.bats b/test/workflows/feature-ideation/lint-prompt.bats
index a0cd32ea..1ba14d1a 100644
--- a/test/workflows/feature-ideation/lint-prompt.bats
+++ b/test/workflows/feature-ideation/lint-prompt.bats
@@ -158,3 +158,57 @@ YML
   run bash "$LINTER" "${TT_TMP}/v1-clean.yml"
   [ "$status" -eq 0 ]
 }
+
+# ---------------------------------------------------------------------------
+# Exit-code precedence: file errors (2) must not be downgraded by later lint
+# findings (1). Caught by CodeRabbit review on PR petry-projects/.github#85.
+# ---------------------------------------------------------------------------
+
+@test "lint-prompt: missing file before lint-failing file still exits 2" {
+  write_yml "${TT_TMP}/bad.yml" <<'YML'
+jobs:
+  analyze:
+    steps:
+      - uses: anthropics/claude-code-action@v1
+        with:
+          prompt: |
+            Date: $(date -u +%Y-%m-%d)
+YML
+  # Pass a non-existent file FIRST, then a file with a lint finding.
+  # The aggregate exit code must be 2 (file error) not 1 (lint finding).
+  run bash "$LINTER" "${TT_TMP}/missing.yml" "${TT_TMP}/bad.yml"
+  [ "$status" -eq 2 ]
+}
+
+@test "lint-prompt: YAML chomping modifiers are recognised (prompt: |-)" {
+  # YAML block-scalar headers like `|-`, `|+`, `>-`, `>+` must be detected
+  # as prompt markers so their bodies are linted. Caught by CodeRabbit on PR #85.
+  write_yml "${TT_TMP}/chomping.yml" <<'YML'
+jobs:
+  analyze:
+    steps:
+      - uses: anthropics/claude-code-action@v1
+        with:
+          prompt: |-
+            Date: $(date -u +%Y-%m-%d)
+YML
+  run bash "$LINTER" "${TT_TMP}/chomping.yml"
+  [ "$status" -eq 1 ]
+}
+
+@test "lint-prompt: GitHub Actions expressions with nested braces do not false-positive" {
+  # ${{ format('${FOO}', github.ref) }} should be stripped entirely so ${FOO}
+  # inside the expression is not flagged as a bare shell expansion.
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  write_yml "${TT_TMP}/nested-expr.yml" <<'YML'
+jobs:
+  analyze:
+    steps:
+      - uses: anthropics/claude-code-action@v1
+        with:
+          prompt: |
+            Ref: ${{ format('{0}', github.ref) }}
+YML
+  run bash "$LINTER" "${TT_TMP}/nested-expr.yml"
+  [ "$status" -eq 0 ]
+}
diff --git a/test/workflows/feature-ideation/match-discussions.bats b/test/workflows/feature-ideation/match-discussions.bats
index 9b63ea9a..b92bce07 100644
--- a/test/workflows/feature-ideation/match-discussions.bats
+++ b/test/workflows/feature-ideation/match-discussions.bats
@@ -192,6 +192,22 @@ build_proposals() {
   [ "$status" -eq 0 ]
 }
 
+@test "match: malformed JSON in signals file exits non-zero" {
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  printf 'not valid json' >"${TT_TMP}/signals.json"
+  build_proposals '[{"title":"x"}]'
+  run bash "$MATCH" "${TT_TMP}/signals.json" "${TT_TMP}/proposals.json"
+  [ "$status" -ne 0 ]
+}
+
+@test "match: malformed JSON in proposals file exits non-zero" {
+  # Caught by CodeRabbit review on PR petry-projects/.github#85.
+  build_signals '[]'
+  printf 'not valid json' >"${TT_TMP}/proposals.json"
+  run bash "$MATCH" "${TT_TMP}/signals.json" "${TT_TMP}/proposals.json"
+  [ "$status" -ne 0 ]
+}
+
 @test "match: idempotent re-run of same proposals against existing matches yields all-matched" {
   # Simulates the R6 idempotency case: run 1 created Discussions, run 2
   # finds them and should NOT propose duplicates.
diff --git a/test/workflows/feature-ideation/signals-schema.bats b/test/workflows/feature-ideation/signals-schema.bats
index 0281d589..4ad05181 100644
--- a/test/workflows/feature-ideation/signals-schema.bats
+++ b/test/workflows/feature-ideation/signals-schema.bats
@@ -69,6 +69,15 @@ FIX="${TT_FIXTURES_DIR}/expected"
   [ "$status" -eq 0 ]
 }
 
+@test "schema: malformed JSON signals file FAILS with exit code 2" {
+  # Validates that the OSError/JSONDecodeError path returns 2 (file/data error)
+  # not 1 (schema validation error). Caught by CodeRabbit review on PR #85.
+  bad_file="${BATS_TEST_TMPDIR}/malformed.json"
+  printf '{"schema_version":"1.0.0",' >"$bad_file"
+  run python3 "$VALIDATOR" "$bad_file" "$SCHEMA"
+  [ "$status" -eq 2 ]
+}
+
 @test "schema: SCHEMA_VERSION constant matches schema file version comment" {
   # CodeRabbit on PR petry-projects/.github#85: enforce that the
   # SCHEMA_VERSION constant in collect-signals.sh stays in lockstep with
diff --git a/test/workflows/feature-ideation/stubs/gh b/test/workflows/feature-ideation/stubs/gh
index 2e8cd24d..27584df2 100755
--- a/test/workflows/feature-ideation/stubs/gh
+++ b/test/workflows/feature-ideation/stubs/gh
@@ -31,8 +31,15 @@ if [ -n "${GH_STUB_LOG:-}" ]; then
 fi
 
 # Multi-call mode.
+# NOTE: TT_TMP (or BATS_TEST_TMPDIR as fallback) must be set so the counter
+# file is isolated per test. Without it the fallback /tmp path can collide
+# across parallel test suites. Caught by CodeRabbit review on PR #85.
+if [ -n "${GH_STUB_SCRIPT:-}" ] && [ ! -f "${GH_STUB_SCRIPT}" ]; then
+  printf '[gh-stub] GH_STUB_SCRIPT is set but file not found: %s\n' "$GH_STUB_SCRIPT" >&2
+  exit 1
+fi
 if [ -n "${GH_STUB_SCRIPT:-}" ] && [ -f "${GH_STUB_SCRIPT}" ]; then
-  counter_file="${TT_TMP:-/tmp}/.gh-stub-counter"
+  counter_file="${TT_TMP:-${BATS_TEST_TMPDIR:-/tmp}}/.gh-stub-counter"
   count=0
   if [ -f "$counter_file" ]; then
     count=$(cat "$counter_file")