[FEATURE]: NULLS (NOT) DISTINCT for Postgres Unique Indexes

[curiosbasant]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

A very useful new-ish feature (afaict, Postgres 15) is NULLS NOT DISTINCT in Postgres unique indexes.
https://www.postgresql.org/docs/current/indexes-unique.html

That is already supported for unique but not for uniqueIndex in drizzle-orm.
https://orm.drizzle.team/docs/indexes-constraints#unique

The API can definitely be same as unique

export const userNulls = pgTable('table', {
    courseId: uuid().references(() => course.id),
    lessonId: uuid().references(() => lesson.id),
}, (t) => [{
  unq: uniqueIndex().on(t.courseId, t.lessonId).nullsNotDistinct()
}]);