some refactoring in intermediate representation and sql extraction

mitm_tooling/definition/__init__.py

mitm_tooling/definition/definition_representation.py

mitm_tooling/extraction/sql/data_models/db_meta.py

mitm_tooling/extraction/sql/data_models/virtual_view.py

mitm_tooling/extraction/sql/mapping/export.py

mitm_tooling/extraction/sql/mapping/mapping.py

mitm_tooling/io/exporting.py

mitm_tooling/representation/intermediate/__init__.py

mitm_tooling/representation/intermediate/deltas.py

mitm_tooling/representation/intermediate/header.py

mitm_tooling/representation/intermediate_representation.py

mitm_tooling/representation/sql_representation.py

mitm_tooling/transformation/sql/from_intermediate.py

mitm_tooling/transformation/sql/into_exportable.py

mitm_tooling/transformation/sql/into_mappings.py

pyproject.toml

test/something.py