feat: Add avatar deletion functionality and update ProfileScreen to handle avatar presence

app/src/main/java/com/rosetta/messenger/repository/AvatarRepository.kt

@@ -167,6 +167,43 @@ class AvatarRepository(
         }
     }
     
+    /**
+     * Удалить свой аватар
+     */
+    suspend fun deleteMyAvatar() {
+        withContext(Dispatchers.IO) {
+            try {
+                Log.d(TAG, "🗑️ deleteMyAvatar called")
+                Log.d(TAG, "👤 Current public key: ${currentPublicKey.take(16)}...")
+                
+                // Получаем все аватары пользователя
+                val avatars = avatarDao.getAvatarsByPublicKey(currentPublicKey)
+                
+                // Удаляем файлы
+                for (avatar in avatars) {
+                    try {
+                        AvatarFileManager.deleteAvatar(context, avatar.avatar)
+                        Log.d(TAG, "✅ Deleted avatar file: ${avatar.avatar}")
+                    } catch (e: Exception) {
+                        Log.w(TAG, "⚠️ Failed to delete avatar file: ${avatar.avatar}", e)
+                    }
+                }
+                
+                // Удаляем из БД
+                avatarDao.deleteAllAvatars(currentPublicKey)
+                Log.d(TAG, "✅ Avatars deleted from DB")
+                
+                // Очищаем memory cache
+                memoryCache.remove(currentPublicKey)
+                
+                Log.d(TAG, "🎉 Avatar deleted successfully!")
+            } catch (e: Exception) {
+                Log.e(TAG, "❌ Failed to delete avatar: ${e.message}", e)
+                throw e
+            }
+        }
+    }
+    
     /**
      * Загрузить и расшифровать аватар из файла
      */