[vinayagg]

What broke
Bees startup could wait for account and directory sync before serving the UI. Opening or switching threads also waited for fresh data instead of showing the saved conversation immediately.

Why
Startup awaited the initial account refresh, and conversation access checks shared the wider organization and billing refresh path.

What changed

• Open the UI with saved thread and directory data before starting background setup and sync.
• Start optional dependency setup after the browser paints, sync the selected conversation first, then start remaining account sync and schedules. Keep a fallback for headless clients.
• Show cached conversations immediately when switching threads, with a background sync indicator and protection against late responses replacing the current selection.
• Keep cached views read-only until refreshed, isolate caches by account, cache only remote conversation text, and remove revoked previews after directory refresh.
• Separate conversation directory checks from organization and billing updates, and keep private local reads independent of the network.

Tested

• npm run check passed, including desktop tests, type checking, and desktop/hosted UI builds.
• Focused tests cover startup ordering with pending dependency setup, cached data across restart, revoked previews, reads during stalled background sync, rapid thread switches, and account isolation.
• Isolated runtime smoke test with a deliberately stalled organization sync: saved-data snapshot in 1.95 seconds, cached conversation read in 6 ms, selected startup sync in 60 ms, and another conversation read in 32 ms while background sync stayed blocked. These are local API timings, not rendered UI timings.
• Packaged fresh-install UI timing has not been tested.