fix(desktop): stop windows from adopting each other's active project

Every window shares one server settings document, and every PUT returns the
merged whole, so one window's activeProjectId write was adopted by the
other on its next unrelated settings save — its sidebar then auto-selected
a session in that project and wrote the pointer back, converging both
windows onto one session. settings-synced now carries an adoptWorkspace
flag: only bootstrap-grade syncs (startup, runtime switch) may adopt the
shared workspace pointers; reconcile responses keep the window's own active
project while it exists. Notification clicks and session deep links also
stopped broadcasting the session switch to every window.

packages/ui/src/components/auth/SessionAuthGate.tsx

@@ -353,6 +353,7 @@ export const SessionAuthGate: React.FC<SessionAuthGateProps> = ({
   const [activePasskeyAction, setActivePasskeyAction] = React.useState<'auth' | 'register' | null>(null);
   const passwordInputRef = React.useRef<HTMLInputElement | null>(null);
   const hasResyncedRef = React.useRef(skipAuth);
+  const hasBootstrapResyncedRef = React.useRef(skipAuth);
 
   React.useEffect(() => {
     if (typeof window === 'undefined') {
@@ -593,10 +594,18 @@ export const SessionAuthGate: React.FC<SessionAuthGateProps> = ({
     }
     if (state === 'authenticated' && !hasResyncedRef.current) {
       hasResyncedRef.current = true;
+      // First authentication of this page load is bootstrap: adopt the
+      // persisted workspace pointers. A re-login after mid-session expiry is
+      // not — this window already has its own workspace, and the shared
+      // settings document may carry another window's pointers.
+      const isBootstrapResync = !hasBootstrapResyncedRef.current;
+      hasBootstrapResyncedRef.current = true;
       void (async () => {
         await initializeAppearancePreferences();
-        await syncDesktopSettings();
-        await applyPersistedDirectoryPreferences();
+        await syncDesktopSettings({ adoptWorkspace: isBootstrapResync });
+        if (isBootstrapResync) {
+          await applyPersistedDirectoryPreferences();
+        }
       })();
     }
   }, [skipAuth, state]);