vercel: Reuse existing OpenAI code (#33362)

Follow up to #33292

Since Vercel's API is OpenAI compatible, we can reuse a bunch of code.

Release Notes:

- N/A
18f1221a44Bennet Bo Fenner committed on 6/25/2025, 1:04:43 PM· committed by GitHubparentc979452
6 files changedLine totals unavailable