Returns delivery history in reverse chronological order. Each entry includes the timestamp, event type, company ID, response status, response body (truncated to 1000 characters), test flag, and round-trip duration in milliseconds. Supports standard DRF limit/offset pagination (default page size: 500, max: 500). Optionally filter by webhook_id and/or is_test. Only deliveries for webhooks owned by the authenticated user are returned.