fix: quiesce cancelled session reconciliation

packages/session-query/session-query-sqlite/README.md

@@ -34,7 +34,7 @@ The database is disposable but reset is guarded: every recognized schema version
 
 The index uses FTS5 `unicode61`. In the implementation experiment it supported the two-character query `AI` and produced an index about 2.1× smaller than the trigram alternative. The trade-off is token/phrase recall rather than arbitrary substring recall: `AI` does not match the token `BRAID`. Use `ctx.sessionQuery.filterEvents()` with a `text` clause when a literal whitespace-flexible substring scan is required. NUL is rejected in queries; reserved highlight markers and NUL in documents are normalized before indexing so presentation markers cannot collide with source text.
 
-Abort signals stop queued work and caller waits around asynchronous source observation. Node's synchronous `DatabaseSync` API cannot interrupt a MATCH statement already executing on the JavaScript thread; the signal is checked immediately before and after the serialized observation/reconciliation boundary.
+Abort signals stop queued work and flow unchanged through snapshot listing and non-mutating inspection. Once source work starts, the serialized state machine awaits that backend promise itself—even when a backend ignores cancellation—then checks the signal before starting any further listing, inspection, reconciliation, or query work. The caller therefore observes cancellation only after started backend work is quiescent, and a later search cannot enter the serializer while that cleanup is pending. Node's synchronous `DatabaseSync` API cannot interrupt a metadata or MATCH statement already executing on the JavaScript thread; signals are checked immediately before and after those non-preemptible calls.
 
 ## Model Experience