* feat: Use DATANODE_LEASE_SECS from distributed_time_constants for heartbeat pause duration
* feat: introduce `RegionFailureDetectorController` to manage region failure detectors
* feat: add `RegionFailureDetectorController` to `DdlContext`
* feat: add `region_failure_detector_controller` to `Context` in region migration
* feat: register region failure detectors during rollback region migration procedure
* feat: deregister region failure detectors during drop table procedure
* feat: register region failure detectors during create table procedure
* fix: update meta config
* chore: apply suggestions from CR
* chore: avoid cloning
* chore: rename
* chore: reduce the size of the test
* chore: apply suggestions from CR
* chore: move channel initialization into `RegionSupervisor::channel`
* chore: minor refactor
* chore: rename ident
* test: add e2e test for region failover
* chore: add ci cfg
* chore: reduce parallelism to 8
* fix(ci): enable region failure
* chore: set sqlx LogLevel to Off
* refactor: move help functions to utils