This moves some of the changes made in
https://github.com/zed-industries/zed/pull/39543 to the `publish_gpui`
script.
This PR also updates that script to use `gpui_` instead of `zed-` (where
possible)
Release Notes:
- N/A
Expands on #38543 (notably allows setting importance categories and
weights on tests, and a lot of internal refactoring) because I couldn't
help myself. Also allows exporting runs to json and comparing across them. See code for docs.
Release Notes:
- N/A