Integration tests for profilers: mssql, oracle, legacy_synapse, bigquery, snowflake, redshift

[m-abulazm]

Scope

Integration test coverage in tests/integration/assessments/ is synapse-only. Add integration coverage for the six uncovered profilers, matching the synapse-test patterns

Live-connection tests (requires sandbox infra)

Pattern: similar to the existing tests/integration/cli/test_profiler_connection_cli.py::test_profiler_connection_synapse_success.
For each source where a sandbox instance exists

• configure-database-profiler writes a valid credentials file
• execute-database-profiler connects, runs the pipeline, produces a DuckDB extract
• create-profiler-dashboard validates the extract against the per-source validation YAML