feat: hide authorizer for rental orders, auto-set sale type

Rental orders no longer show the "Authorizer Required?" question or
the Authorizer field. The sale type is automatically set to 'Rentals'
when creating or confirming a rental order. Validation logic also
skips authorizer checks for rental sale type.

Made-with: Cursor

fusion_rental/models/cancellation_request.py

@@ -67,7 +67,10 @@ class RentalCancellationRequest(models.Model):
     def action_confirm(self):
         """Confirm the cancellation and stop auto-renewal."""
         self.ensure_one()
-        self.order_id.write({'rental_auto_renew': False})
+        self.order_id.write({
+            'rental_auto_renew': False,
+            'rental_auto_renew_off_reason': f"Customer requested cancellation ({self.reason or 'No reason provided'})",
+        })
         self.write({'state': 'confirmed'})
         self._schedule_pickup_activity()
         self._send_cancellation_confirmation()