feat: pdo pool hooks

src/Attribute/BuildsPDOPoolConnection.php

src/PDOPool.php

src/PDOPoolConnectionBuilder.php

src/PDOPoolConnectionBuilderCollection.php

src/PDOPoolConnectionBuilderInterface.php

src/SingletonCollection.php

...etonProvider/DatabaseConnectionPoolRepositoryProvider.php

...onProvider/PDOPoolConnectionBuilderCollectionProvider.php