fix: move WorkspaceAuthGate to LayoutDefault for proper re-login hand… (#8381)

## Summary

- Move WorkspaceAuthGate from App.vue to LayoutDefault.vue so it only
wraps authenticated routes
- Change initialize() to run in onMounted() for proper Vue lifecycle
- Restore immediate: true in cloudRemoteConfig watcher as backup
- Gate now mounts fresh after login, fixing re-login feature flag issue

The root cause was a race condition: after logout + page reload, the
cloudRemoteConfig watcher could be set up after the user already logged
in, missing the isLoggedIn change and never calling /features endpoint.

┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-8381-fix-move-WorkspaceAuthGate-to-LayoutDefault-for-proper-re-login-hand-2f66d73d36508182a3dec09a49214a00)
by [Unito](https://www.unito.io)

Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

src/extensions/core/cloudRemoteConfig.ts

@@ -16,15 +16,16 @@ useExtensionService().registerExtension({
     const { isLoggedIn } = useCurrentUser()
     const { isActiveSubscription } = useSubscription()
 
-    // Refresh config when subscription status changes
-    // Initial auth-aware refresh happens in WorkspaceAuthGate before app renders
+    // Refresh config when auth or subscription status changes
+    // Primary auth refresh is handled by WorkspaceAuthGate on mount
+    // This watcher handles subscription changes and acts as a backup for auth
     watchDebounced(
       [isLoggedIn, isActiveSubscription],
       () => {
         if (!isLoggedIn.value) return
         void refreshRemoteConfig()
       },
-      { debounce: 256 }
+      { debounce: 256, immediate: true }
     )
 
     // Poll for config updates every 10 minutes (with auth)