Follow-up on the salvaged #110928 (CLI `--parent-chat-id` / `--guild-id`):
- `_claim_for_sub` skipped a thread-shaped row that matched no `profile_routes`
entry at DEBUG on every tick. Legacy rows written before the flags existed can
never match a channel-level route (no `parent_chat_id`), so the notifier now
logs ONE WARNING per row naming the task, the thread and the re-subscribe
command. Still fail-closed: the events stay unclaimed.
- Docs: the kanban user guide explains the anchors and shows the Discord-thread
subscribe command under `profile_routes`.
- Test (red on origin/main): two collects → exactly one WARNING, events unseen.
a21747fe4e