Two related reliability fixes.
1. routes/chat.py — guard run_generation against uncaught exceptions.
run_generation is launched with asyncio.create_task(); any exception
raised inside the coroutine is silently swallowed by the event loop,
the buffer stays in GenerationState.RUNNING forever, and every
subsequent POST /api/chat/conversations/<id>/messages returns 409
'Generation already in progress' — locking the user out of the chat
with no log trail.
Observed in dev 2026-05-22: assistant message 768 created at 20:36:59
with status=generating, stayed in that state for an hour+, and four
follow-up message attempts returned 409 instantly. The generation
task hung before any internal log line could fire, so the only
diagnostic was the 409 responses themselves.
Wrap run_generation in _run_generation_guarded() that catches
exceptions, logs with full traceback, transitions the buffer to
ERRORED, emits a final 'done' SSE event so any active stream
client closes cleanly, and marks the assistant message status=error
in the DB. After this, a stuck conversation recovers on its own
the next time the user sends a message — no manual DB poke needed.
2. services/curator_scheduler.py — pass last_curator_run_at as 'since'
to the curator so each sweep only sees messages added after the
previous successful pass.
Previously the scheduler called run_curator_for_conversation(conv_id)
with no 'since' argument, so the curator defaulted to its 24h
lookback window. Within an active journal session that meant every
15-min sweep re-extracted beats from messages already captured
on prior sweeps — producing duplicate moments.
_candidate_conversations() now returns (conv_id, last_curator_run_at)
tuples; _sweep() threads the timestamp through. First-run case
(last_curator_run_at IS NULL) falls back to the curator's default
24h window, which is what we want — process recent backlog on
first contact, then only deltas after.
Manual trigger path (POST /api/journal/curator/run/<conv_id>) is
intentionally NOT changed; it still passes since=None so the
24h re-sweep behaviour is preserved for ad-hoc 'reprocess today'
clicks from the UI.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>