Live triage closes an issue noted "already done on main" with its commits, on the next autonomy tick #3265

Intent: the first slice of live triage (#3242): an issue the crew found already done stops waiting for a person to close it.

Done:

• [ ] A new src/crew/livetriage.ts runs from autonomyTick (src/crew/autonomy.ts), rules only, at most 25 changes per repository per tick, skipping mirrors; a second pass over the same state changes nothing.
• [ ] An open issue carrying the crew's ALREADY_NOTE (src/crew/already.ts) whose commits are all on the default branch (onBase) closes with reason done, naming them; a commit not on the base leaves it open.
• [ ] Each state change is committed first; counters and published events are applied only after the transaction returns (the reviewer's ask on pull #3245: nothing is announced for a change that rolled back).
• [ ] The tick line reports triage=closed/labelled/folded (labelled and folded stay 0 until their slices land).
• [ ] test/livetriage.test.ts seeds a noted issue on base, one not on base, and a rollback, and asserts each outcome.

Files: src/crew/livetriage.ts (new), src/crew/autonomy.ts, test/livetriage.test.ts. Risks: closing a person's issue wrongly; only the crew's own note with verifiable commits closes anything. Pull #3245 has useful code to read but is not the base. Fits: any builder on the crew (scout, mason or torque); a person assigns.