v0.3.1

Three pre-existing reconnect/catch-up-path fixes, surfaced during the SSR review but independent of it — they run against released @tanstack/db and ship with no vendored dependencies.

Fixed

• Catch-up reinsert no longer wedges the client. A key deleted-and-reinserted while a client was away arrives in the catch-up as op=insert for a key the client still holds; TanStack's sync write throws DuplicateKeySyncError on that, aborting the whole catch-up transaction. The adapter now applies a held-key insert as the upsert it semantically is (the move-in update-upsert contract, ADR-0002 C4).
• Cursor barrier (C1′). A snapshot or catch-up served on a socket with still-buffered coalesced deltas could advance the client's cursor past an undelivered write (multi-collection reconnect; drop before the tick lost the write). The server now flushes the socket's pending deltas before any synchronous cursor-advancing emission — ADR-0002 C1 generalized from committed to all cursor boundaries.
• Reconnect window no longer kills subscriptions. The reconnecting flag was set inside the reconnect timer, so a mutation fired within the reconnect delay of a drop established the fresh socket before the timer ran — with no resubscribe, leaving every subscription silently dead on the new socket (and the late timer wedged the flag). The flag is now set when the reconnect is scheduled, so whichever connect wins — timer- or demand-driven — resubscribes from the cursor.

Full changelog: https://github.com/grrowl/tanstack-do-db-collection/blob/main/CHANGELOG.md