docs(board): CosmicFest is clean, and it settles the suffix question

Ran the new generation lens proactively against Cosmic26_master, before that
release goes anywhere: 12 OK, zero stale, zero strays. The exact opposite of
OPAL, for two reasons that are lessons rather than luck — only one render
generation exists on disk, and every permalink is gig-scoped via
--permalink-suffix, so no CosmicFest upload could collide with the OPAL cut of
the same score. Four of these titles exist at both gigs.

That answers an open board decision with evidence instead of taste. It asked
whether to keep OPAL unsuffixed for consistency; the suffixed release has 0
permalink pathologies and the unsuffixed one has 14. Consistency with a broken
scheme is not a virtue, so new OPAL uploads get suffixed. The 6 correct
unsuffixed tracks stay — they are right, and renaming spends a permalink for
nothing.

Found in passing: CosmicFest is missing exactly 2 tracks, and they are almost
certainly the two already-known vanishers that logged '✓ live at', passed an API
check, then 404'd. A plain idempotent re-run converges. Which is the standing
lesson landing on its feet: verify the shelf AFTER a run, not only during it —
'N uploaded, 0 failed' was never evidence that N tracks exist, and it took a
lens three weeks later to notice two were gone.

TASKS_DUMP.md

@@ -2101,3 +2101,62 @@ staging, or was it itself drift? If deliberate, it is gone and wants restoring
 (`feedback_gig_gain_staging`: source peaks at −6 dBFS, let FOH amplify). If it was
 drift, this is now the cleanest that session has been. One listen decides it, and
 only he can.
+
+## 🔍 CosmicFest-26 checked with the same lens — CLEAN, and it settles the suffix question
+
+Ran `sc_generation_lens.py` against `Cosmic26_master` proactively, before that
+release goes anywhere. Verdicts in
+`sc_pull_2026-09-05/cosmic26_generation_verdicts.json`:
+
+```
+OK 12 · stale 0 · strays 0 · coincidences dropped 0 · never uploaded 2
+```
+
+**Zero stale, zero strays** — the opposite of OPAL. Two reasons, and both are
+lessons rather than luck:
+
+1. **Only ONE render generation exists** (`tracks_v1_streaming`). Nothing to
+   confuse. OPAL had three on disk and all three reached the account.
+2. **The permalinks are gig-scoped** — every one ends `-cosmicfest-2026`, from
+   `build_release_plan.py --permalink-suffix`. So no CosmicFest upload could ever
+   collide with, or be mistaken for, the OPAL cut of the same score — and four of
+   these titles (Take Five, Piment, Sunshine, Eh ouais je Funk) exist at both gigs.
+
+### ✅ This ANSWERS the open suffix-policy decision, with evidence
+
+The board asked whether to keep OPAL unsuffixed for consistency. Compare the two
+releases as they actually sit on the account today:
+
+| | permalinks | stale/strays |
+|---|---|---|
+| CosmicFest-26 | gig-scoped (`-cosmicfest-2026`) | **0** |
+| OPAL-26 | unsuffixed | **14** |
+
+Consistency with a broken scheme is not a virtue. **Suffix OPAL's remaining
+uploads too.** The 6 already-correct unsuffixed tracks can stay as they are
+(they are right, and renaming costs a permalink for nothing) — but every NEW
+upload should be gig-scoped, because a livecoded catalogue replays titles by
+design and a global namespace will collide again on the next gig.
+
+### 🔴 CosmicFest needs exactly 2 re-uploads, and we already know why
+
+```
+/am-i-doing-it-right-cosmicfest-2026   396.69s   NOT UPLOADED
+/vague-de-crime-cosmicfest-2026        252.00s   NOT UPLOADED
+```
+
+**These are almost certainly the two known vanishers**, not new failures — see
+`topic_soundcloud`: two CosmicFest tracks logged `✓ live at`, were verified by
+API, then 404'd on `/resolve` and were absent from `/users/{id}/tracks`. Both
+FLACs decode with zero ffmpeg errors and `/me.quota` was fine, so it is SC-side
+and **a plain re-run converges** — `form-album` is idempotent and will skip the
+12 that are already up.
+
+This is also the standing lesson in action: *verify the shelf AFTER a run, not
+only during it.* "N uploaded, 0 failed" from the uploader was not evidence that
+N tracks exist, and it took a lens run three weeks later to notice two were gone.
+
+⚠️ Still gated on PLN either way: the board's rule is **do not upload
+CosmicFest's split before he approves the tone**, and that approval has not
+landed. The 2 missing tracks are a re-run, not a new release decision — but they
+are part of a release he has not signed off.