Follow-up to @de1tydev's poll-read-only fix. Removing the
_completion_consumed.add() from poll() fixes the gateway/tui watcher
suppression (#10156) but reintroduces the CLI duplicate that #8228 fixed:
a notify_on_complete process always enqueues a completion event, and the
CLI idle/post-turn drain would re-inject it as a [SYSTEM: ...] message
even though the agent already saw the exit inline in its poll result.
Add a separate _poll_observed set that poll() populates on an observed
exit. drain_notifications() (CLI only) skips poll-observed sessions; the
gateway/tui watchers keep checking only is_completion_consumed, so a
read-only poll never suppresses their autonomous delivery turn.
- _poll_observed pruned alongside _completion_consumed in _prune_if_needed
- 4 tests: CLI drain dedup after poll, gateway gate untouched, running
poll doesn't mark observed, wait/log still skip CLI drain
Teknium
41ba90f814