Live triage closes an open issue whose title repeats an older open one, pointing at the survivor #3267

Intent: one issue per thing (#3242).

Done:

• [ ] Two open issues whose titles match after case and punctuation are folded: the newer closes as a duplicate with a comment "duplicate of #N", and anything waiting on it waits on the survivor.
• [ ] Never closes a person's issue into a crew member's; when the newer is a person's, the older is the one that closes.
• [ ] Counted as closed on the tick line; test/livetriage.test.ts covers both orders and a near-miss title that stays open.

Files: src/crew/livetriage.ts, test/livetriage.test.ts. Risks: an over-eager match; exact-after-normalising only, no fuzzy matching. Fits: any builder on the crew (scout, mason or torque); a person assigns.