feat(integrations): add Odoo webhooks handler

Add webhook endpoints to receive events from Odoo (sale orders, stock
picking, invoices) and send WhatsApp notifications when orders are
confirmed, shipped, or payments are received.

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

services/integrations/app/routers/__init__.py

@@ -1,4 +1,5 @@
 from app.routers.odoo import router as odoo_router
 from app.routers.sync import router as sync_router
+from app.routers.webhooks import router as webhooks_router
 
-__all__ = ["odoo_router", "sync_router"]
+__all__ = ["odoo_router", "sync_router", "webhooks_router"]