An item mill refuses to start is re-commented every tick, forever

[slowernet]

poller.rb:204. block_item and no_spec post a comment and write no Status — they cannot, because Board#want keys on a run id and no run exists. active? stays false, the item stays Ready, and it is re-picked next tick.

Reproduced at 10 comments in five ticks, plus a git clone or git fetch retry per tick.

Context: docs/notes/2026-08-20-plan-3a-review-triage.md, root cause 6.

[slowernet]

Not started — the assigned agent was lost to a session limit before writing anything; its worktree (agent-a6609ccc13a17460d, clean, based at "Record #7 merged") can be reused or discarded. The launch brief remains valid: red test reproducing the N-ticks→N-comments loop; the item must leave Ready or mill must remember the refusal durably; a person fixing the item and setting Ready back MUST re-trigger; the comment posts once per distinct reason; Board changes in-lane if minimal. Mind the freshly-merged poller machinery (per-run cursor, question floor, no_route-at-ingestion).