feat(assistant): Improve screen context processing with model selection

lib/core/utils/android_assistant_handler.dart

@@ -40,7 +40,7 @@ class AndroidAssistantHandler {
   Future<void> _handleMethodCall(MethodCall call) async {
     if (call.method == 'analyzeScreen') {
       final String context = call.arguments as String;
-      _ref.read(screenContextProvider.notifier).setContext(context);
+      await _processScreenContext(context);
     } else if (call.method == 'analyzeScreenshot') {
       final String screenshotPath = call.arguments as String;
       await _processScreenshot(screenshotPath);
@@ -49,6 +49,34 @@ class AndroidAssistantHandler {
     }
   }
 
+  Future<void> _processScreenContext(String context) async {
+    try {
+      DebugLogger.log('Processing screen context', scope: 'assistant');
+
+      // Wait for app to be ready (authenticated and model available)
+      final navState = _ref.read(authNavigationStateProvider);
+      final model = _ref.read(selectedModelProvider);
+
+      if (navState != AuthNavigationState.authenticated || model == null) {
+        DebugLogger.log('App not ready for screen context processing', scope: 'assistant');
+        return;
+      }
+
+      // Navigate to chat if not already there
+      final isOnChatRoute = NavigationService.currentRoute == Routes.chat;
+      if (!isOnChatRoute) {
+        // Navigation will happen via auth state
+        return;
+      }
+
+      // Set the screen context
+      _ref.read(screenContextProvider.notifier).setContext(context);
+      DebugLogger.log('Screen context set successfully', scope: 'assistant');
+    } catch (e) {
+      DebugLogger.log('Failed to process screen context: $e', scope: 'assistant');
+    }
+  }
+
   Future<void> _processScreenshot(String screenshotPath) async {
     try {
       DebugLogger.log('Processing screenshot: $screenshotPath', scope: 'assistant');

lib/features/chat/views/chat_page.dart

@@ -315,12 +315,10 @@ class _ChatPageState extends ConsumerState<ChatPage> {
       // Clear the context so we don't process it again
       WidgetsBinding.instance.addPostFrameCallback((_) {
         ref.read(screenContextProvider.notifier).setContext(null);
-        // Pre-fill the input or send a message
+        final currentModel = ref.read(selectedModelProvider);
-        // For now, let's just pre-fill the input with a prompt
-        // TODO: Ideally we should add this as a system message or attachment
         _handleMessageSend(
           "Here is the content of my screen:\n\n$screenContext\n\nCan you summarize this?",
-          null,
+          currentModel,
         );
       });
     }