refactor(storage): convert SQLFavoriteStorage to actor

Author: datlechin

CHANGELOG.md

@@ -25,7 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
-- Storage and sync singletons accept dependencies via init for test isolation, matching Apple's URLSession and UserDefaults convention. Production callers using `.shared` are unchanged.
+- Storage and sync singletons accept dependencies via init for test isolation, matching Apple's URLSession and UserDefaults convention. Production callers using `.shared` are unchanged. `SQLFavoriteStorage` is now an actor so its first access no longer blocks the main thread on SQLite setup.
 - Create Database dialog is now driver-driven. Each driver discovers its own valid options (PostgreSQL queries `pg_collation` and `pg_database`, MySQL/MariaDB query `information_schema.character_sets`/`collations`). The hardcoded macOS-flavored locale list is gone. Engines that don't support creation hide the Create button instead of failing on click.
 - Introduced TableRows, Row, and Delta value types in TablePro/Models/Query/ as the foundation for the data grid row model rewrite. No callers migrated yet (Phase C.1 of the DataGrid refactor).
 - DataGrid columns and cells refactored to use a persistent column pool and typed cell view hierarchy. CPU usage on table switch reduced significantly through proper NSTableView reuse pool retention.