refactor: Update Note and Category models to use 'id' instead of 'uuid', and adjust related database operations

- Changed 'uuid' to 'id' in Note and Category models for consistency.
- Updated database operations in NoteRepository to reflect the new 'id' field.
- Modified sync models to accommodate changes in Note and Category structures.
- Adjusted the handling of notes and categories during synchronization.
- Refactored the note editor and home screen to use the new 'id' field.
- Ensured that the 'isDirty' flag is properly set and utilized across models.

lib/screens/note_editor_screen.dart

@@ -89,7 +89,7 @@ class _NoteEditorScreenState extends State<NoteEditorScreen> {
   @override
   void initState() {
     super.initState();
-    _isNewNote = widget.note?.id == null;
+    _isNewNote = widget.note == null;
 
     if (_isNewNote) {
       final DateTime now = DateTime.now();
@@ -98,7 +98,7 @@ class _NoteEditorScreenState extends State<NoteEditorScreen> {
         body: '',
         createdAt: now,
         updatedAt: now,
-        index: 0,
+        position: 0,
       );
     } else {
       _currentNote = widget.note!;
@@ -143,6 +143,7 @@ class _NoteEditorScreenState extends State<NoteEditorScreen> {
       title: title.isEmpty ? 'Sin título' : title,
       body: body,
       updatedAt: DateTime.now(),
+      isDirty: true,
     );
 
     _complete(updatedNote);