v1.2.4

• Ship compatible ClickHouse v1 DDL for the outbox routes, using
  ReplacingMergeTree ORDER BY event_id and separate event_at /
  ingested_at timestamps.
• Change the zero-argument route defaults to distinct ab_outbox_exposures and
  ab_outbox_conversions tables. The old defaults collided with the direct
  sink's incompatible schema; explicit custom names remain supported.
• Add a live clean-install integration path from trackers through SQLite-backed
  yii3-outbox-db and yii3-outbox-clickhouse into the shipped tables.