feat(desktop): enhance error handling and logging for session synchronization and window mode transitions

apps/desktop-client/src/renderer/App.vue

@@ -30,7 +30,14 @@ function getModeBridge(): WindowModeBridge | undefined {
 }
 
 function syncWindowMode(authenticated: boolean): void {
-  void getModeBridge()?.setWindowMode?.(authenticated ? 'main' : 'login', { source: 'auth-state' })
+  void getModeBridge()
+    ?.setWindowMode?.(authenticated ? 'main' : 'login', { source: 'auth-state' })
+    .catch((err) => {
+      console.warn('[desktop-app] window mode sync failed', {
+        authenticated,
+        message: err instanceof Error ? err.message : String(err),
+      })
+    })
 }
 
 const rendererWindowMode = resolveRendererWindowMode()
@@ -62,7 +69,11 @@ if (rendererWindowMode === 'main') {
 
 onMounted(() => {
   if (rendererWindowMode !== 'login') {
-    void syncRuntimeSession()
+    void syncRuntimeSession().catch((err) => {
+      console.warn('[desktop-app] runtime session sync failed', {
+        message: err instanceof Error ? err.message : String(err),
+      })
+    })
   }
   if (usesAutomaticWindowMode) {
     syncWindowMode(isAuthenticated.value)