Replace fire-and-forget key delivery with a sync-status protocol that
verifies key consistency between main thread and Service Worker using
SHA-256 fingerprints via MessageChannel request-response.
- SW (ts/sw.ts): persist keys in IndexedDB, auto-restore on activate;
respond to sync-status queries with loaded keys + fingerprints;
support cryptio-clear-keys to wipe memory + DB.
- New ts/utils/swSync.ts: single entry point for SW registration,
key sync, and status verification. Controller change listener
re-syncs on SW restart. Deduplicates concurrent sync calls.
- Deleted ts/utils/swKeySender.ts (replaced by swSync.ts).
- Remove SW registration (~55 lines) from cryptioSaveImage.ts;
setup() now calls syncSWStatus().
- uploadUtils.ts: drop 5-retry preview loop (~6.4s worst case);
single attempt with syncSWStatus fallback on failure.
- cryptioSettings.ts: sync after key changes; clearSWKeys() on
Clear All.
- cryptioUploadImage/Video.ts: syncSWStatus in setup + preview
fallback.
- types.ts: add SWStatus interface.
Suzu008