#511 Migrate work-types to a JSON SSOT with schema validation

[williamthorsen]

What

Replaces the work-types markdown table with a structured JSON SSOT validated by a JSON Schema, expands the vocabulary from 11 types in PRIMARY/SECONDARY/TERTIARY tiers to 15 types in public/internal/process tiers, and introduces a per-type breakingPolicy field (forbidden | optional | required) that decouples the breaking-marker rule from tier. The taxonomy now includes drop, deprecate, sec, and perf as first-class public-tier types alongside the existing feat and fix, aligning with conventional-changelog ecosystems and unblocking downstream tooling that needs to derive constants from this list.

Why

Downstream tools (e.g., the upcoming drift-detection check in node-monorepo-tools) need to consume the work-types vocabulary programmatically. Parsing the previous markdown table was brittle and made cross-repo drift detection noisy with formatting differences. The previous file also mixed structural data (rows) and prose (rules and carve-outs) — two concerns with different lifecycles — and the legacy PRIMARY/SECONDARY/TERTIARY tier vocabulary did not map cleanly onto conventional-changelog ecosystems that downstream tooling targets.

Details

Refactoring

• New packages/agents/content/skills/_data/work-types.json carries 15 types in canonical render order, each with key, aliases, tier, emoji, label, and breakingPolicy fields. fmt carries excludedFromChangelog: true.
• New packages/agents/schemas/work-types.schema.json (JSON Schema draft 2020-12) constrains data shape with additionalProperties: false everywhere and uses prefixItems with per-slot const plus items: false on the tiers array, so positional order — which encodes tiebreak precedence — is enforced structurally rather than by an in-test assertion.
• The previous _data/work-types.md is removed; its prose (precedence rule, breaking-change rule, AI-instructions carve-out) moves into commit/SKILL.md grouped by the new tiers, with a precedence rule rewritten around tier order ("dominant purpose; tiebreak by higher tier, then earlier listing within tier") and a per-type breaking-change rule that lists which types fall under each breakingPolicy value.
• summarize-change/SKILL.md and .agents/PROJECT.md updated to reference the new JSON path and tier-order phrasing.

Tests

• New packages/agents/src/lib/__tests__/work-types-schema.test.ts validates the live work-types.json against the schema, exercises rejection cases for unknown top-level keys, malformed key/version patterns, out-of-enum tier and breakingPolicy values, missing required fields, and a misordered tiers array, and asserts globally unique aliases plus canonical types[] render order.
• packages/agents/src/lib/__tests__/content-resolver.test.ts adds an assertion that skills/_data/work-types.json exists in the resolved content directory, anchoring the guarantee that codeassembly-agents install ships the file into ~/.claude/skills/_data/.

Test plan

• Verify the rendered changelog/release notes for this PR draw from ## What cleanly.
• Confirm node-monorepo-tools can fetch work-types.json and work-types.schema.json via the raw.githubusercontent.com URL pattern at the agreed tag.

Closes #511

[github-actions]

Dependency audit

Production dependency audit passed.