release: v0.5.2

[graydawnc]

What

Patch release rolling up the merged work since v0.5.1:

PR	Summary
#346	Collapse bulk purge into a single transaction — closes #344 (60s freeze)
#347	Schema v14: dedupe (session_id, msg_uuid) + UNIQUE INDEX
#348	Switch syncer to append-only — purge / dismiss state now survives re-sync
#349	"Refresh from source" — explicit per-session rebuild action
#350	Batch scan-worker enqueue burst into one status publish
#351	Smooth the scan-end visual transition (unified ScanStatusBanner)
#352	Move purge / dismiss / undismiss SQL onto a worker thread + late-attach plumbing

Why

Cuts a patch version so the bulk-purge UX fix from #344 actually reaches users — the 60s → main-thread-responsive arc only matters in real installs. Same release also picks up the append-only sync semantic that makes Security Scan state durable across the natural "re-sync the session after a new turn" lifecycle.

No schema or IPC contract changes beyond what already landed in v0.5.1's migration v13 → v0.5.2's migration v14. Schema migration is idempotent and runs once on first launch.

Verification

Each underlying PR's CI was green at merge; this release branch only bumps version in 6 package.json files. No code changes ride along.