[FEATURE]: native support for postgres unnest

### 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

Doing batch inserts via `insert` is painful due to limitations in postgres.
I tried improving the situation here: https://github.com/drizzle-team/drizzle-orm/pull/5400, but eventually it boils down to this pattern being quite limited.

The alternatives are `copy`, which has it's own limitations and select `unnest`.
Working with unnest from drizzle is a pain though, as you basically need to write raw sql and opt out drizzle i guess.
```
INSERT INTO balance_deltas ("user", delta)
SELECT * FROM unnest(
${sql.param(users)}::text[],
${sql.param(deltas)}::numeric(78,0)[]
)
ON CONFLICT ("user")
DO UPDATE SET delta = balance_deltas.delta + excluded.delta
```

I feel like it would be great to have some better native integration, like `db.insert().unnestValues()` or similar.