feat(ui): unified Tasks surface, 6-destination rail & sidebar removal (#606)

[IBondarenko-iwg]

Linked issue

Closes #606

Summary of changes

Part 3 of 4 of the #551 navigation-shell rollout (R1, v4.1) — the tab restructure and unified Tasks surface.

Outpost

• Rail 7 → 6 destinations (Overview · Tasks · Product · Decisions · Workflows · Settings, PRD order). The Roadmap pipeline board and the Processes tab fold into a new Tasks surface: status filter chips with live count badges (All · Todo · Analysing · Needs input · Analysed · In progress · Done · Skipped), single task list with status-word rows and inline task actions, slim detail panel on row click ("Full detail" opens the existing 6-section modal), running processes as a section below — processes.js reused verbatim.
• Contextual sidebar fully removed (completes the promise from feat(ui): render v4 navigation shell in Outpost and Mothership dashboard (#605) #624). Content re-homed: Control/Session/Git/panic → Overview cockpit column; product nav + project card → Product pane; workflow tree (Studio button rides along) → Workflows pane; decision counts + New Decision → Decisions header; settings nav → Settings pane. layout.js trimmed to its storage helpers (shell.js's rail pin depends on them).
• Decision counts are now filter chips (design spec 10 names Decisions as the chip example), status colours preserved.
• Installed-workflow pills dropped from the topbar (spec 7.3 default — isolated commit 6fe2c17, one-revert if the pending question on Navigation shell: tab restructure + unified Tasks surface #606 resolves the other way). Current-workflow badge stays; installedWorkflows still feeds the launch CTA.
• Search pill centered mid-bar and widened per the spec 7.3 sketch.

Mothership: dashboard's 3 in-page tabs restyled as sentence-case filter chips (CSS-only, same switching JS).

Notable deviations (documented, not accidental)

1. Needs-input + All + Skipped chips = superset of PRD's 5-chip list (dropping them would lose operator capability)
2. Cancelled = count-only text — /api/state carries no cancelled_list; follow-up for StateBuilder
3. Done list server-capped at 20 (recent_completed) while the badge shows the full count — inherited, now labelled
4. Delete action retained beyond PRD's edit/history/ignore/restore list (capability preservation)
5. Processes as a section vs literal "single task list" (processes ≠ tasks; Q3 model — no task↔process correlation data exists)
6. Workflows pane not strictly "read-only": nav tree carries run/stop buttons (capability preservation over wording)
7. Studio button degradation = click-time toast, not hide/disable (PRD 5.4 wording; availability pre-check deferred — new API surface)
8. "Workflows" label kept vs PRD's "Workflow"
9. Mothership chips = restyle only; spec 8's full single-surface absorb deferred (per the Index.cshtml breadcrumb left in Navigation shell: top bar + icon rail rendered in both Studio and Mothership #605)
10. Search-pill sizing supersedes Navigation shell: dotbot-shell.css + standalone HTML harness + shared-CSS serving #604's fixed min-width (shared-CSS change, both apps)
11. Fixed pre-existing off-theme Test button (dead .btn classes) + three layout bugs found during review (pane scroll clipping, runs-panel flex squeeze, nav-column page inflation)

Known follow-up candidates (not in scope): make run-card task rows link to the Tasks detail panel (they were never clickable); cancelled_list in /api/state; #553 wires the search pill / Ctrl+K.

Screenshots / recordings

Where did Roadmap and Processes go?

Before: Roadmap (kanban)	Before: Processes	After: unified Tasks

Overview → cockpit

Before	After

More surfaces: Workflows · Settings · Decisions chips · mobile 480px · Mothership

Workflows pane (nav re-homed, runs panel fixed)

Before	After

Settings (nav re-homed)

Before	After

Decisions — counts are now filter chips (after only; tab unchanged in the before-set)

Product

Before	After

Mobile 480px (no drawer — panes stack, cockpit first)

Before	After

Mothership — tabs restyled as chips

Before	After

Testing notes

• E2E: 23/23 passed on the final run (tests/Test-UI-E2E.ps1) — including 3 new tasks.spec.ts tests (chip filtering, detail panel + modal, action-button guard) and both historically flaky tests.
• Browser-verified: all 6 rail destinations; every chip's badge count matches its filtered rows (needs-input combines input+review waiting per Surface needs-review tasks in the Needs Input pipeline section #500); workflow filter populates; New Task / Deleted / edit / ignore / delete / history+restore reachable from rows and panel; process rows expand/whisper/stop/kill from the Tasks surface; Overview RUN/STOP + panic + git commit; Studio button; decision chips filter the list; duplicate-ID audit clean; no page errors in any probe.
• Layout regressions checked at 1620/1440/1300/480px: no topbar clipping, panes scroll with tall content, nav columns scroll independently, cockpit column reads as a framed scrollable panel.
• Respond/Confirmation and all Mothership markup/JS untouched except the chip CSS (git diff — dashboard.css only).

Checklist

• Tests added or updated
• Linked issue exists
• Follows the contribution guide