Refactor payment flow to use database triggers (Clean Architecture)

BREAKING CHANGE: Complete refactor of payment handling

New Architecture:
1. pakasir-webhook (120 lines -> was 535 lines)
   - Only verifies signature and updates order status
   - Removed: SMTP, email templates, notification logic

2. Database Trigger (NEW)
   - Automatically fires when payment_status = 'paid'
   - Calls handle-order-paid edge function
   - Works for webhook AND manual admin updates

3. handle-order-paid (NEW edge function)
   - Grants user access for products
   - Creates Google Meet events for consulting
   - Sends notifications via send-email-v2
   - Triggers webhooks

Benefits:
- Single Responsibility: Each function has one clear purpose
- Trigger works for both webhook and manual admin actions
- Easier to debug and maintain
- Reusable notification system

Migration required: Run 20241223_payment_trigger.sql

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

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

supabase/migrations/20241223_payment_trigger.sql

@@ -0,0 +1,93 @@
+-- ============================================================================
+-- Payment Trigger Architecture
+-- ============================================================================
+-- This refactors the payment flow to use database triggers instead of
+-- handling everything in the webhook function.
+--
+-- Flow:
+-- 1. pakasir-webhook or admin updates order.payment_status = 'paid'
+-- 2. Trigger fires -> calls handle_paid_order() function
+-- 3. handle_paid_order() calls handle-order-paid edge function
+-- 4. Edge function handles: access grants, notifications, meet links
+-- ============================================================================
+
+-- Enable pg_net extension for HTTP calls from PostgreSQL
+CREATE EXTENSION IF NOT EXISTS pg_net;
+
+-- ============================================================================
+-- Function: handle_paid_order
+-- Purpose: Called by trigger when order payment_status becomes 'paid'
+-- Calls the edge function to handle all post-payment actions
+-- ============================================================================
+CREATE OR REPLACE FUNCTION handle_paid_order()
+RETURNS TRIGGER AS $$
+DECLARE
+  edge_function_url TEXT;
+  edge_function_response TEXT;
+  order_data JSON;
+BEGIN
+  -- Only proceed if payment_status changed to 'paid'
+  IF (NEW.payment_status != 'paid' OR OLD.payment_status = 'paid') THEN
+    RETURN NEW;
+  END IF;
+
+  -- Log the payment event
+  RAISE NOTICE 'Order % payment status changed to paid', NEW.id;
+
+  -- Get the edge function URL from environment
+  edge_function_url := current_setting('app.base_url', true) || '/functions/v1/handle-order-paid';
+
+  -- Prepare order data
+  order_data := json_build_object(
+    'order_id', NEW.id,
+    'user_id', NEW.user_id,
+    'total_amount', NEW.total_amount,
+    'payment_method', NEW.payment_method,
+    'payment_provider', NEW.payment_provider
+  );
+
+  -- Call the edge function asynchronously via pg_net
+  -- We use pg_net to avoid blocking the transaction
+  PERFORM net.http_post(
+    url := edge_function_url,
+    headers := json_build_object(
+      'Content-Type', 'application/json',
+      'Authorization', 'Bearer ' || current_setting('app.service_role_key', true)
+    ),
+    body := order_data
+  );
+
+  RAISE NOTICE 'Called handle-order-paid for order %', NEW.id;
+
+  RETURN NEW;
+EXCEPTION
+  WHEN OTHERS THEN
+    -- Log error but don't fail the transaction
+    RAISE WARNING 'Failed to call handle-order-paid for order %: %', NEW.id, SQLERRM;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+-- ============================================================================
+-- Trigger: on_order_paid
+-- Purpose: Fires handle_paid_order() when order payment status changes
+-- ============================================================================
+DROP TRIGGER IF EXISTS on_order_paid ON orders;
+
+CREATE TRIGGER on_order_paid
+  AFTER UPDATE ON orders
+  FOR EACH ROW
+  WHEN (NEW.payment_status = 'paid' AND OLD.payment_status IS DISTINCT FROM NEW.payment_status)
+  EXECUTE FUNCTION handle_paid_order();
+
+-- ============================================================================
+-- Comments for documentation
+-- ============================================================================
+COMMENT ON FUNCTION handle_paid_order() IS 'Triggered when order payment_status becomes "paid". Calls handle-order-paid edge function to handle access grants, notifications, and Meet link creation.';
+COMMENT ON TRIGGER on_order_paid ON orders IS 'Fires handle_paid_order() function when payment status changes to paid';
+
+-- ============================================================================
+-- Grant necessary permissions
+-- ============================================================================
+GRANT EXECUTE ON FUNCTION handle_paid_order() TO postgres;
+GRANT USAGE ON SCHEMA net TO postgres;