* refactor(native-chat): remove the records-file and per-chat journal imports
Every native chat user is on a build that already moved chat records and
history into the app-wide database, so the one-time copies are dead code:
the agent-sessions.json import and its owed-copy flag, the per-chat
journal.db import and the write-queue hold behind it, and the pre-SQLite
log.jsonl notice.
* refactor(native-chat): remove what only the deleted imports used
- JournalHostDatabase.unsyncedTransaction and the synchronous-pragma reset
that undid it; JOURNAL_SYNCHRONOUS is now module-local. The stranded
rollback test drives transaction() instead.
- deleteUnpublishedJournalRows and its SQL, plus its test.
- boundJournalStatusText.
- Stale comments naming the removed first-use copy (queued messages,
send refusal example, JOURNAL_SYNCHRONOUS doc).
- Write-queue and readInOrder comments: a write also lags when issued
behind one still waiting in line.
- Resolved-append ordering test binds the sink from inside a running read,
so a resolver that read at handover now fails it.
* test(native-chat): run resolved-append in the SQLite runtime project