agent: Read the user's plan from the `UserStore` (#29305)

This PR updates the Agent panel to read the user's plan from the
`UserStore` instead of hard-coding it.

Release Notes:

- N/A
d095bab8adMarshall Bowers committed on 4/23/2025, 10:27:11 PM· committed by GitHubparentf8c3fe7
1 file changedLine totals unavailable