Signing out no longer dumps you on a /sign-in 404

There was a frustrating bug in the sign-out flow: under certain conditions, after clicking Sign out, you ended up staring at a 404 page on /sign-in. The cause was a stale service worker cache that kept serving an outdated route table after the session cookie had been cleared.

Sign-out now forces a full service-worker and cache cleanup as part of the same operation. The session cookie goes, the cache flushes, the worker re-registers, and the redirect lands you cleanly on the live /sign-in page every single time.

If you have been hitting that 404, it should be gone. And if you have ever switched accounts on the same machine and then seen the previous user's dashboard for a split second, that class of bug is fixed too.