Define audit rules, severity classification, scanning strategies, and report templates for data integrity validation. Covers: - Schema validity (PostgreSQL tables, columns, types) - dbt project health (parse, compile, test, lineage) - PostGIS compliance (SRID, geometry types, extent) - Data type consistency (DataFrame dtypes) - Query safety patterns Closes #373 Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>