refactor: optimize startup

lib/core/providers/app_providers.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -207,9 +208,12 @@ final socketServiceProvider = Provider<SocketService?>((ref) {
         authToken: token,
         websocketOnly: transportMode == 'ws',
       );
-      // best-effort connect; errors handled internally
+      // best-effort connect, but defer to post-frame with a small delay
-      // ignore unawaited_futures
+      WidgetsBinding.instance.addPostFrameCallback((_) async {
+        await Future.delayed(const Duration(milliseconds: 150));
+        // ignore: discarded_futures
         s.connect();
+      });
       // Keep socket token up-to-date without reconstructing the service
       ref.listen<String?>(authTokenProvider3, (prev, next) {
         s.updateAuthToken(next);
@@ -881,24 +885,28 @@ final backgroundModelLoadProvider = Provider<void>((ref) {
   // Ensure API token updater is initialized
   ref.watch(apiTokenUpdaterProvider);
 
-  // Schedule background loading without blocking
+  // Only run when authenticated, and defer until after first frame
+  final navState = ref.read(authNavigationStateProvider);
+  if (navState != AuthNavigationState.authenticated) {
+    return;
+  }
+
+  WidgetsBinding.instance.addPostFrameCallback((_) {
+    // Schedule background loading without blocking startup frame
     Future.microtask(() async {
-    // Wait a bit to ensure auth is complete
+      // Small delay to allow initial build/layout to settle
-    await Future.delayed(const Duration(milliseconds: 200));
+      await Future.delayed(const Duration(milliseconds: 250));
 
       DebugLogger.log('bg-start', scope: 'models/background');
-
-    // Load default model in background
       try {
         await ref.read(defaultModelProvider.future);
         DebugLogger.log('bg-complete', scope: 'models/background');
       } catch (e) {
-      // Ignore errors in background loading
         DebugLogger.error('bg-failed', scope: 'models/background', error: e);
       }
     });
+  });
 
-  // Return immediately, don't block the UI
   return;
 });
 

lib/core/providers/app_startup_providers.dart

@@ -149,12 +149,16 @@ final appStartupFlowProvider = Provider<void>((ref) {
   Future.microtask(() async {
     final online = ref.read(isOnlineProvider);
     if (!online) return;
+    // Slightly increase jitter to reduce contention on startup
     final jitter = Duration(
-      milliseconds: 50 + (DateTime.now().millisecond % 100),
+      milliseconds: 150 + (DateTime.now().millisecond % 200),
     );
+    // Defer until after first frame to keep first paint smooth
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
       await Future.delayed(jitter);
       _scheduleConversationWarmup(ref);
     });
+  });
 
   // One-time, post-frame system UI polish: set status bar icon brightness to
   // match theme after the first frame. Avoids flicker at startup.

lib/core/services/connectivity_service.dart

@@ -33,13 +33,14 @@ class ConnectivityService {
   bool get isCurrentlyConnected => _lastStatus == ConnectivityStatus.online;
 
   void _startConnectivityMonitoring() {
-    // Initial check after a slightly longer delay to avoid competing with
+    // Initial check after a brief delay to avoid showing offline during startup
-    // first-frame work. Start periodic checks only after the first probe.
+    Timer(const Duration(milliseconds: 800), () {
-    Timer(const Duration(milliseconds: 1200), () async {
-      await _checkConnectivity();
-      _connectivityTimer = Timer.periodic(_interval, (_) {
       _checkConnectivity();
     });
+
+    // Check periodically; interval adapts to recent failures
+    _connectivityTimer = Timer.periodic(_interval, (_) {
+      _checkConnectivity();
     });
   }
 

lib/core/services/share_receiver_service.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter/foundation.dart';
+import 'package:flutter/widgets.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:share_handler/share_handler.dart' as sh;
 
@@ -72,7 +73,10 @@ final shareReceiverInitializerProvider = Provider<void>((ref) {
     () => maybeProcessPending(),
   );
 
-  // Hook into share_handler
+  // Hook into share_handler after a short defer to avoid startup contention
+  WidgetsBinding.instance.addPostFrameCallback((_) async {
+    await Future.delayed(const Duration(milliseconds: 300));
+
     final handler = sh.ShareHandler.instance;
 
     // Handle initial share when app is cold-started via Share
@@ -113,6 +117,7 @@ final shareReceiverInitializerProvider = Provider<void>((ref) {
       await streamSub.cancel();
     });
   });
+});
 
 SharedPayload _toPayload(dynamic media) {
   if (media == null) return const SharedPayload();

lib/main.dart

@@ -55,12 +55,12 @@ void main() {
       _startupTimeline!.start('app_startup');
       _startupTimeline!.instant('bindings_initialized');
 
-      // Enable edge-to-edge globally (back-compat on pre-Android 15)
+      // Defer edge-to-edge mode to post-frame to avoid impacting first paint
-      // Pairs with Activity's EdgeToEdge.enable and our SafeArea usage.
+      WidgetsBinding.instance.addPostFrameCallback((_) {
-      // Do not block first frame on system UI mode; apply shortly after startup
         // ignore: discarded_futures
         SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
-      _startupTimeline!.instant('edge_to_edge_enabled');
+        _startupTimeline?.instant('edge_to_edge_enabled');
+      });
 
       final sharedPrefs = await SharedPreferences.getInstance();
       _startupTimeline!.instant('shared_prefs_ready');