Export a single ticket for audit

Returns an audit-focused CSV export of one ticket: one row per event in strict chronological order with the columns timestamp, actor, actor_email, event_type, detail, content. Covers messages, internal notes, status/assignee/priority/tag changes and automated/system actions; routing (team/assignee) is included in the detail text of the ticket-created and inbox-entered rows. Downloaded as ticket_<bugId>_audit.csv (text/csv).