update(2610.1).sql brings an existing database up to the current schema
without PHP: base tables (CREATE IF NOT EXISTS), the v2603.x migrations
(last_event_at column, uq_event removal) and the v2610.1 index changes
(idx_occurred, idx_src_ip_occ, drop idx_src_ip). All steps are idempotent
via information_schema checks + PREPARE/EXECUTE, so the file is safe to
re-run and portable across MySQL 8 and MariaDB.
