[renderer] Wire epic dashboard to the deterministic renderer

[leeovery]

Summary

Stacked on #351. Makes the epic state display render via the deterministic renderer instead of being hand-drawn inline.

• epic-dashboard.cjs (new) — renderEpicDashboard(epic) assembles the entire dashboard (box title, three stage dividers, one tree per phase, stage-meta callouts) from a buildEpicDetail-shaped object, using the generic renderer ([renderer] Tree shape — discovery-map renderer (spike → keeper) #351) + conventions. Epic-specific composition (lifecycle labels, count summaries, ← source rows, impl progress, seed/import/new-arrival callouts) lives here; titlecase() added to conventions.
• discovery.cjs — new render <work_unit> [new_arrivals_json] command that emits the finished block (the display surface) in-process; the default data-dump output (the reasoning surface) is untouched, so every other consumer is unaffected.
• epic-display-and-menu.md — the "non-empty map" branch drops from ~103 lines (hand-drawn template + the whole "Stage and tree display rules") to 7: run the command, emit verbatim. Net −94 lines of prose. The no-map "Otherwise" branch is kept self-contained (still hand-drawn; wiring it + its recommendation logic is a follow-up).

Intentional visual changes from the old hand-drawing (all previously agreed): ↳ From … provenance, 8-col body gutter, width-72 wrapping with the gutter-orphan bug now impossible.

Test plan

• node --test tests/scripts/test-render.cjs tests/scripts/test-epic-dashboard.cjs — 43 tests (renderer + epic-dashboard: helpers, full render, callouts).
• Renders the full dashboard from a realistic buildEpicDetail fixture; the render command errors cleanly when the work unit isn't an active epic.
• Note: end-to-end against a live .workflows/ manifest is not exercised here (this repo has none); the data path reuses the battle-tested discover().

🤖 Generated with Claude Code

[leeovery]

Winding this back. It was a valuable end-to-end spike — it proved the renderer covers the epic dashboard from real data — but we're pausing the live integration to design the data-handler architecture properly first (one central data handler, per-skill thin entries, schema-driven projections). The diff stays here for reference; renderer core lives in #348/#351.