Completes the turn/session decoupling so nothing is lost across disconnects.
Phase 2 (durability):
- New chat_session_events table (global monotonic id = cursor) + queries
appendChatEvent / getChatEventsSince / pruneChatEventsOlderThan.
- Every durable outbound ServerMessage now goes through emitToSession: appended
to the queue (even while the client is disconnected) and delivered live with
its seq. Streaming deltas stay ephemeral (live-only, never persisted).
Phase 3 (resilient transport):
- New 'resume-cursor' client message → handleResumeCursor re-binds the socket to
the (still-live) session (cancels idle-GC via attachWs) and replays every event
since the client's cursor.
- useChatWebSocket already auto-reconnects; added an onOpen hook. useChat tracks
the max seq and, on every (re)connect with an established session, sends
resume-cursor — so a dropped connection self-heals with no manual navigate
away/back, and background task notifications that landed while offline replay.
Verified end-to-end: disconnect after a turn's result but before a background
task finishes, reconnect with the cursor → the missed task:notification is
replayed from Postgres, no duplicates.
Note: the DB is managed via drizzle push/direct DDL (no __drizzle_migrations
table), so 0001 was applied directly; the generated migration is committed for
the record.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
pastilhasandClaude Opus 4.8
6b3eb247a3