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

composer.json

@@ -8,6 +8,7 @@
     "require": {
         "php": "^8.4",
         "filament/filament": "^5.0",
+        "laravel/cashier": "^16.5",
         "laravel/fortify": "^1.34",
         "laravel/framework": "^13.0",
         "laravel/sanctum": "^4.0",