- Introduced equivalent base types and variants for PostgreSQL types to normalize type comparisons.
- Added functions for normalizing SQL types and retrieving equivalent type variants.
- Updated migration writer to handle type alterations with checks for existing types.
- Implemented logic to create necessary extensions (e.g., pg_trgm) based on schema requirements.
- Enhanced tests to cover new functionality for type normalization and migration handling.
- Improved handling of GIN indexes to use appropriate operator classes based on column types.
* Enhance MergeResult to track added constraints and indexes.
* Update merge logic to increment counters for added constraints and indexes.
* Modify GetMergeSummary to include constraints and indexes in the output.
* Add comprehensive tests for merging constraints and indexes.
