[FEATURE]: Integrate DB Constraints into Drizzle-Zod

### Feature hasn't been suggested before.

- [x] I have verified this feature I'm about to request hasn't been suggested before.

### Describe the enhancement you want to request

I’m currently finding that Zod schemas generated with drizzle-zod require me to re-implement the same constraint checks that already exist in my database, using refine. Ideally, drizzle-zod would incorporate these database constraints directly, avoiding duplicated boilerplate and ensuring a single source of truth.

Start by examining drizzle-zod's schema-generation entry point and how database constraints are represented for the supported SQL dialects. Define which constraints should be reflected in generated Zod schemas, then verify that users no longer need to duplicate those checks with refine.

Written by the indexing model from the issue text.