feat: Add column name mappings option

[FelipeKalinoski]

##PLEASE CAREFULLY REVIEW THE CHANGES BEFORE ACCEPTING IT##

Description of changes

This PR implements support for column name mapping (--column-name-map) across row validation and partition generation. Key changes include:

• ConfigManager Updates: Modified build_config_comparison_fields, build_dependent_aliases, and build_column_configs to correctly resolve source column names to their target equivalents using the mapping provided.
• Calculated Field Refactoring: Updated _get_calculated_config and _get_source/target_ibis_calculated_table to iteratively apply calculated fields, resolving issues where dependencies (like hash__all) were not found when mappings were active.
• System Testing: Added system tests in tests/system/data_sources/test_oracle.py covering row validation with --concat=* and partition generation with mapped primary keys.
• Unit Test Stability: Patched tests/unit/test__main.py to correctly mock GCS directory listing, ensuring local test runs pass without requiring live Google Cloud credentials.

Issues to be closed

Closes #1617

Checklist

• I have followed the CONTRIBUTING Guide.
• I have commented my code, particularly in hard-to-understand areas
• I have updated any relevant documentation to reflect my changes, if applicable
• I have added unit and/or integration tests relevant to my change as needed
• I have already checked locally that all unit tests and linting are passing (use the tests/local_check.sh script)
• I have manually executed end-to-end testing (E2E) with the affected databases/engines (verified via mocked system tests and standalone demo script)

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[nj1973]

I tested the changes and my previously passing test test_column_validation_column_name_map_to_bigquery now fails with a duplicate column error. I need to try and understand the changes you've made to figure out why my test now fails.

[nj1973]

Requested a change to oracle integration tests.

I also need to try and debug the changes for column validation which no longer works.

[nj1973]

Did you add this so you could test without BigQuery?

I tested test_row_validation_column_name_map_to_bigquery without this and it passed.

e.g.:

-@mock.patch("data_validation.clients.get_data_client", side_effect=mock_get_data_client)
+# @mock.patch("data_validation.clients.get_data_client", side_effect=mock_get_data_client)
 @mock.patch(
     "data_validation.state_manager.StateManager.get_connection_config",
     new=mock_get_connection_config,
 )
-def test_row_validation_column_name_map_to_bigquery(mock_get_client):
+# def test_row_validation_column_name_map_to_bigquery(mock_get_client):
+def test_row_validation_column_name_map_to_bigquery():

Ideally I'd rather these integration tests run with real tables and not mocked ones.

I appreciate this makes it harder for you to test but it matches other tests in this file.

Can we remove the mocked client please?

[FelipeKalinoski]

Yes, I did use mock tables for testing without BigQuery. We can delete it.

[FelipeKalinoski]

Requested a change to oracle integration tests.

I also need to try and debug the changes for column validation which no longer works.

@nj1973 did you create a unit test for testing column validation or were you executing a "manual" test?