feat: Add color and icon properties to categories, enhance category management in UI

lib/screens/note_editor_screen.dart

@@ -14,15 +14,25 @@ import 'package:notas/platform/app_platform.dart';
 // the user confirmed deletion. `null` indicates the user closed without saving.
 
 class NoteEditorScreen extends StatefulWidget {
-  const NoteEditorScreen({super.key, required this.note, this.onComplete});
+  const NoteEditorScreen({
+    super.key,
+    required this.note,
+    this.categoryId,
+    this.onComplete,
+  });
 
   final Note? note;
+  final String? categoryId;
   final ValueChanged<dynamic>? onComplete;
 
   @override
   State<NoteEditorScreen> createState() => _NoteEditorScreenState();
 
-  static Future<dynamic> showDialog(BuildContext context, {Note? note}) {
+  static Future<dynamic> showDialog(
+    BuildContext context, {
+    Note? note,
+    String? categoryId,
+  }) {
     if (isAndroid || isIOS) {
       return showGeneralDialog<dynamic>(
         context: context,
@@ -30,7 +40,7 @@ class NoteEditorScreen extends StatefulWidget {
         barrierColor: Colors.transparent,
         transitionDuration: const Duration(milliseconds: 200),
         pageBuilder: (context, animation, secondaryAnimation) {
-          return NoteEditorScreen(note: note);
+          return NoteEditorScreen(note: note, categoryId: categoryId);
         },
         transitionBuilder: (context, animation, secondaryAnimation, child) {
           return ScaleTransition(scale: animation, child: child);
@@ -46,7 +56,7 @@ class NoteEditorScreen extends StatefulWidget {
         barrierColor: Colors.transparent,
         transitionDuration: const Duration(milliseconds: 200),
         pageBuilder: (context, animation, secondaryAnimation) {
-          return NoteEditorScreen(note: note);
+          return NoteEditorScreen(note: note, categoryId: categoryId);
         },
         transitionBuilder: (context, animation, secondaryAnimation, child) {
           return ScaleTransition(scale: animation, child: child);
@@ -61,6 +71,7 @@ class NoteEditorScreen extends StatefulWidget {
       builder: (BuildContext overlayContext) {
         return NoteEditorScreen(
           note: note,
+          categoryId: categoryId,
           onComplete: (dynamic result) {
             if (!completer.isCompleted) {
               completer.complete(result);
@@ -99,6 +110,7 @@ class _NoteEditorScreenState extends State<NoteEditorScreen> {
         createdAt: now,
         updatedAt: now,
         position: 0,
+        categoryId: widget.categoryId,
       );
     } else {
       _currentNote = widget.note!;