docs(board): the release is one re-run from done, plus a pre/post-gig setup plan

Session of 2026-08-17/18 written back to the board for a cold reader, since the
Task API is still unreachable from this session and the scratchpad — which held
the release plan and every log — was cleaned mid-session. (The plan regenerates
from canonical sources, which is exactly why it is a generated artifact; it now
lands in Prod/Opal26_master/release/ rather than /tmp.)

A3 rewritten: the SoundCloud uploader WORKS. `POST /tracks` never needed solving
— it was the wrong door. Recorded the account's verified state (8 of 15 up, all
private, including the 72:41 mix), the two DOM facts that cost a session each,
and two defects a re-run will NOT fix by itself: take-five-drops uploaded 24 s
short, and ghosts-in-the-toilets carries one malformed tag from before the
chip-input fix. Also recorded that api-v2 is a dead end for BOTH create and
update, so nobody re-opens it.

A5: the YouTube adapter is built, with the finding that decides its architecture
— the Data API cannot publish at all from an unaudited project.

New EPIC G (Slopmotion release videos) carries the renderer's two landed fixes
with their measurements, the one modal still blocking, and the 50-commit pull
that inverted the app's mode semantics under us.

New EPIC H is what PLN asked for: the long-term setup plan split into PRE-GIG
(what must be true before playing again — the 59%-audible kick, orphan orbits,
preload staleness, SC supervision, the LCXL v3) and POST-GIG (the release
pipeline). Plus H3, the standing lesson: three confident conclusions this session
were wrong the same way — a blind instrument reported absence — and PLN's own
eyes beat the probes every time.