Add subscription tiers, notification preferences, and logging infrastructure

- Add database migrations for plans, subscriptions, notification preferences, and notification log tables
- Implement DispatchUserNotificationJob to handle channel resolution, daily limits, and logging (sent/tier_restricted/daily_limit)
- Add SendScheduledWhatsAppJob for scheduled notification delivery
- Create PlanFeatures service to resolve tier capabilities, check daily limits, and validate fuel

app/Models/User.php

@@ -58,4 +58,14 @@ class User extends Authenticatable implements FilamentUser
     {
         return $this->hasMany(SavedStation::class);
     }
+
+    public function notificationPreferences(): HasMany
+    {
+        return $this->hasMany(UserNotificationPreference::class);
+    }
+
+    public function notificationLogs(): HasMany
+    {
+        return $this->hasMany(NotificationLog::class);
+    }
 }