collab: Add LLM request overage columns to `billing_preferences` (#29446)

This PR adds two new columns to the `billing_preferences` table to allow
users to opt in to overages on LLM requests.

Release Notes:

- N/A
8b910e1cd9Marshall Bowers committed on 4/25/2025, 8:43:43 PM· committed by GitHubparent12c645e
2 files changedLine totals unavailable