Delete workflow trigger

Permanently delete a workflow trigger. This will stop the workflow from executing automatically based on this trigger.

After deletion:

• For inbound_message triggers: Messages to the phone_number_id will no longer start this workflow
• For api_call triggers: The workflow can still be started manually via POST /workflows/{id}/executions

This operation cannot be undone. If you need to temporarily disable a trigger, use PATCH to set active=false instead.