[FEATURE]: ability to skip policies

### 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

Due to https://github.com/drizzle-team/drizzle-orm/issues/3504, I moved all the `pgPolicy` functions in the schema to a policies.sql file that I execute manually to craete all the policies.

But when I run `drizzle-kit push` it wants to drop all the policies. Is there a way I can let it skip the policies?

Start with the drizzle-kit push flow and the pgPolicy definitions moved into policies.sql. Trace how push detects and plans policy drops, then check the schema and migration documentation for existing skip mechanisms. Done means users can run push without unwanted policy drops while retaining the manually managed policies.

Written by the indexing model from the issue text.