Add Next.js admin panel and implement background worker jobs

- Add full Next.js admin panel with:
  - User, residence, task, contractor, document management
  - Notifications and notification preferences management
  - Subscriptions and auth token management
  - Dashboard with stats
  - Lookup tables management (categories, priorities, statuses, etc.)
  - Admin user management

- Implement background worker job handlers:
  - HandleTaskReminder: sends push notifications for tasks due within 24h
  - HandleOverdueReminder: sends push notifications for overdue tasks
  - HandleDailyDigest: sends daily summary of pending tasks
  - HandleSendEmail: processes email sending jobs
  - HandleSendPush: processes push notification jobs

- Make worker job schedules configurable via environment variables:
  - TASK_REMINDER_HOUR, TASK_REMINDER_MINUTE (default: 20:00 UTC)
  - OVERDUE_REMINDER_HOUR (default: 09:00 UTC)
  - DAILY_DIGEST_HOUR (default: 11:00 UTC)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

internal/config/config.go

@@ -20,6 +20,7 @@ type Config struct {
 	Push     PushConfig
 	Worker   WorkerConfig
 	Security SecurityConfig
+	Storage  StorageConfig
 }
 
 type ServerConfig struct {
@@ -87,6 +88,14 @@ type SecurityConfig struct {
 	MaxPasswordResetRate int // per hour
 }
 
+// StorageConfig holds file storage settings
+type StorageConfig struct {
+	UploadDir    string // Directory to store uploaded files
+	BaseURL      string // Public URL prefix for serving files (e.g., "/uploads")
+	MaxFileSize  int64  // Max file size in bytes (default 10MB)
+	AllowedTypes string // Comma-separated MIME types
+}
+
 var cfg *Config
 
 // Load reads configuration from environment variables
@@ -157,10 +166,10 @@ func Load() (*Config, error) {
 			FCMServerKey: viper.GetString("FCM_SERVER_KEY"),
 		},
 		Worker: WorkerConfig{
-			TaskReminderHour:    viper.GetInt("CELERY_BEAT_REMINDER_HOUR"),
-			TaskReminderMinute:  viper.GetInt("CELERY_BEAT_REMINDER_MINUTE"),
-			OverdueReminderHour: 9,  // 9:00 AM UTC
-			DailyNotifHour:      11, // 11:00 AM UTC
+			TaskReminderHour:    viper.GetInt("TASK_REMINDER_HOUR"),
+			TaskReminderMinute:  viper.GetInt("TASK_REMINDER_MINUTE"),
+			OverdueReminderHour: viper.GetInt("OVERDUE_REMINDER_HOUR"),
+			DailyNotifHour:      viper.GetInt("DAILY_DIGEST_HOUR"),
 		},
 		Security: SecurityConfig{
 			SecretKey:            viper.GetString("SECRET_KEY"),
@@ -169,6 +178,12 @@ func Load() (*Config, error) {
 			ConfirmationExpiry:   24 * time.Hour,
 			MaxPasswordResetRate: 3,
 		},
+		Storage: StorageConfig{
+			UploadDir:    viper.GetString("STORAGE_UPLOAD_DIR"),
+			BaseURL:      viper.GetString("STORAGE_BASE_URL"),
+			MaxFileSize:  viper.GetInt64("STORAGE_MAX_FILE_SIZE"),
+			AllowedTypes: viper.GetString("STORAGE_ALLOWED_TYPES"),
+		},
 	}
 
 	// Validate required fields
@@ -218,9 +233,17 @@ func setDefaults() {
 	viper.SetDefault("APNS_TOPIC", "com.example.mycrib")
 	viper.SetDefault("APNS_USE_SANDBOX", true)
 
-	// Worker defaults
-	viper.SetDefault("CELERY_BEAT_REMINDER_HOUR", 20)
-	viper.SetDefault("CELERY_BEAT_REMINDER_MINUTE", 0)
+	// Worker defaults (all times in UTC)
+	viper.SetDefault("TASK_REMINDER_HOUR", 20)    // 8:00 PM UTC
+	viper.SetDefault("TASK_REMINDER_MINUTE", 0)
+	viper.SetDefault("OVERDUE_REMINDER_HOUR", 9)  // 9:00 AM UTC
+	viper.SetDefault("DAILY_DIGEST_HOUR", 11)     // 11:00 AM UTC
+
+	// Storage defaults
+	viper.SetDefault("STORAGE_UPLOAD_DIR", "./uploads")
+	viper.SetDefault("STORAGE_BASE_URL", "/uploads")
+	viper.SetDefault("STORAGE_MAX_FILE_SIZE", 10*1024*1024) // 10MB
+	viper.SetDefault("STORAGE_ALLOWED_TYPES", "image/jpeg,image/png,image/gif,image/webp,application/pdf")
 }
 
 func validate(cfg *Config) error {