feat(career): gigs frontend — poster, runner strip, summary, encore

Career v3, WS3 (frontend half), rebuilt cleanly on merged main (v3-a/b/c
in) after git interleaved the structurally-similar canvas functions:

- Book a gig from any opened passport: /gigs/propose renders as a GIG
  POSTER (venue presents GENRE NIGHT, numbered bill) with re-roll and
  Save/Copy poster (natively-drawn canvas via blob-io, audible failure
  paths, slash-safe filenames).
- Play the gig: venue override + Venue viz handoff, then
  playQueue.start(..., {source:'gig'}) — the queue's auto-advance runs
  the set; zero new playback machinery.
- Floating gig strip (body-level, pointer-events none, z 35 per the
  chrome invariant) tracks set position and names what's next.
- Completion = song:ended with an empty queue → POST /gigs → summary
  poster overlay with per-song accuracies; encore fires the crowd
  celebrate + confetti (reduced-motion: neither). song:stop with a dead
  queue = abandoned (no log); end-of-song teardown (queue still active)
  must NOT abandon.
- Gigs played render as dated rows in the passport book.

vm tests: runner advance/abandon semantics via the queue-state seam.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+- **Gigs (the career verb, frontend)** — book a gig from any opened passport:
+  a gig poster proposes the setlist (re-roll for a different bill; save or
+  copy the poster as a PNG), "Play the gig" hands the set to the play queue
+  with the venue on stage, a floating strip tracks the set, and finishing it
+  logs dated entries with per-song accuracies in the passport book — with an
+  encore celebration (crowd eruption + confetti) when the whole set clears
+  the bar, and a summary poster to share. Quitting mid-set simply abandons
+  it: no log, no fail state.
 - **Career on the Profile and Home pages** — the Profile gains a passport
   wall (earned-badge covers per instrument, hours, gig count; absent until a
   passport exists), injected through the same mount-point + rendered-event