Save the note leader save the world

internal/repository/notes.go

@@ -35,5 +35,14 @@ func (r *NoteRepository) ListNotes() ([]models.Note, error) {
 }
 
 func (r *NoteRepository) UpdateNote(id int, content string) (models.Note, error) {
-	return models.Note{}, fmt.Errorf("not implemented")
+	if content == "" {
+		return models.Note{}, fmt.Errorf("content cannot be empty")
+	}
+	note, err := r.store.GetNoteByID(id)
+	if err != nil {
+		return models.Note{}, err
+	}
+	note.Content = content
+	note.LastUpdate = time.Now()
+	return r.store.SaveNote(note)
 }