collab: Set `plan` in LLM token based on subscription (#29231)

This PR updates the `plan` field in the LLM token to be based on the
subscription.

We weren't using this field anywhere outside of the new billing code, so
it is safe to change its meaning.

Release Notes:

- N/A
9bbc2e0fb2Marshall Bowers committed on 4/22/2025, 7:44:16 PM· committed by GitHubparent6caf34a
2 files changedLine totals unavailable