inline_completion_button: Replace `UserStore` with `CloudUserStore` (#35456)

This PR replaces usages of the `UserStore` in the inline completion
button with the `CloudUserStore`.

Release Notes:

- N/A
f7f90593acMarshall Bowers committed on 8/1/2025, 3:25:23 AM· committed by GitHubparent8be3f48
4 files changedLine totals unavailable