fix: prevent logout 401 and login double-attempt caused by LWW layout push race

resetUserStores() was abusing populateFromReady('', [], [], []) to clear the
space store. Its LWW timestamp logic fired an async pushLayoutToOrigin when
_layoutUpdatedAt > 0, which read a null token from localStorage (already
removed on logout, not yet set on login). The 401 response triggered
handleUnauthorized(), deleting the freshly-stored login token and forcing a
full page reload — requiring users to log in twice.

Replace with a proper reset() method that synchronously sets all state to
initial values with no LWW comparison or API side effects.

packages/web/src/stores/authStore.ts

@@ -31,7 +31,7 @@ interface AuthState {
 function resetUserStores() {
   clearSelfIds();
   useChatStore.getState().clearAllMessages();
-  useSpaceStore.getState().populateFromReady('', [], [], []);
+  useSpaceStore.getState().reset();
   useSocialStore.getState().reset();
   useVoiceStore.getState().resetSession();
   useInstanceStore.getState().reset();