Covert Flow Schema to Doctrine Dbal Schema

[norberttech]

Just like with #1353 we want to be able to convert flow schema into dbal schema.

The converter should live in Doctrine Adapter and should also provide database related metadata like:

• Flow\ETL\Adapter\Doctrine\Metadata::DEFAULT - mixed
• Flow\ETL\Adapter\Doctrine\Metadata::LENGTH - int
• Flow\ETL\Adapter\Doctrine\Metadata::PRIMARY_KEY - string
• Flow\ETL\Adapter\Doctrine\Metadata::UNIQUE - bool
• Flow\ETL\Adapter\Doctrine\Metadata::INDEX - string `
• Flow\ETL\Adapter\Doctrine\Metadata::PLATFORM_OPTIONS - array<mixed>
• Flow\ETL\Adapter\Doctrine\Metadata::COLUMN_DEFINITION - array<mixed>