`metabase.search` namespace (#42487)

* Search API namespace

* Search API namespace

* Search API namespace

* Fix Kondo warnings

* Fix typo

* Finally solve the MySQL ^:parallel test failures <3

* Make some search tests REPL-friendly

* Did I finally fix `^:parallel` MySQL tests?

* Ok I give up just make the search tests single-threaded for MySQL/MariaDB.

* Revert the stuff to make paralell tests work for MySQL... for now.

* Keep new name

* Revert deps-graph changes

* Remove unused namespaces

* Fix Kondo linter for log/info + format

* Misc fixes 

* Test fixes