refactor: Improve code formatting and replace print with debugPrint for error logging

lib/app.dart

@@ -101,7 +101,8 @@ class _NotesAppState extends State<NotesApp>
     }
 
     final AppPalette palette = _activePalette();
-    final String message = _syncErrorMessage ?? _syncDetailMessage ?? 'Sincronizando...';
+    final String message =
+        _syncErrorMessage ?? _syncDetailMessage ?? 'Sincronizando...';
     final double? progress = _syncProgress;
     final IconData icon;
     final Color accentColor;
@@ -138,7 +139,9 @@ class _NotesAppState extends State<NotesApp>
         child: Container(
           padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
           decoration: BoxDecoration(
-            border: Border(top: BorderSide(color: accentColor.withValues(alpha: 0.45))),
+            border: Border(
+              top: BorderSide(color: accentColor.withValues(alpha: 0.45)),
+            ),
           ),
           child: Column(
             mainAxisSize: MainAxisSize.min,
@@ -591,17 +594,15 @@ class _NotesAppState extends State<NotesApp>
         if (available) {
           bool activated = await _vaultService.enableBiometricProtection();
           while (!activated) {
-            // Ask the user to retry or skip
-            final BuildContext? dialogCtx = _navigatorKey.currentContext;
-            if (dialogCtx == null) {
-              break;
-            }
+            // Ask the user to retry or skip - pass currentContext directly in builder
+            final NavigatorState? navigator = _navigatorKey.currentState;
 
-            final NavigatorState navigator = Navigator.of(dialogCtx);
+            if (navigator == null) break;
+            if (!mounted) return;
 
             final bool? retry = await showDialog<bool>(
-              context: dialogCtx,
-              builder: (BuildContext context) {
+              context: context,
+              builder: (BuildContext dialogContext) {
                 final AppPalette palette = _activePalette();
                 return AlertDialog(
                   backgroundColor: palette.cardBackground,
@@ -1076,10 +1077,11 @@ class _NotesAppState extends State<NotesApp>
                       switchOutCurve: Curves.easeInCubic,
                       transitionBuilder:
                           (Widget child, Animation<double> animation) {
-                            final Animation<Offset> slideAnimation = Tween<Offset>(
-                              begin: const Offset(0.0, 0.35),
-                              end: Offset.zero,
-                            ).animate(animation);
+                            final Animation<Offset> slideAnimation =
+                                Tween<Offset>(
+                                  begin: const Offset(0.0, 0.35),
+                                  end: Offset.zero,
+                                ).animate(animation);
 
                             return FadeTransition(
                               opacity: animation,