Retrieve ticket metric events and measure SLA breach timing via the Zendesk Ticket Metric Events API

Verified steps

1. Send a GET to /api/v2/ticket_metric_events with a start_time Unix timestamp to retrieve metric events incrementally; the endpoint uses time-based cursor pagination.
2. Parse each event's metric field (first_reply_time, next_reply_time, agent_work_time, on_hold_time) along with the instance_id that links related start, pause, resume, and fulfill events for the same SLA metric on the same ticket.
3. To reconstruct elapsed SLA time for a ticket, group events by ticket_id and instance_id, then sum the intervals between activate/start and pause events, and between resume and fulfill/breach events.
4. Identify breached events by looking for metric event records where type is breach; complement this with the fulfilled_at and breached_at timestamps if present in the event payload.
5. Cross-reference metric events with the SLA policy attached to the ticket (from the ticket's sla_policy field) to understand whether business hours were in effect for a given metric.
6. Store the end_time cursor from each response page as the start_time for the next incremental pull; this endpoint is designed for event-stream processing rather than full historical pulls.