no issue
The marketplace still uses the `/settings/theme/install` route but that was removed as part of the redesign for design settings.
- added `settings.design.change-theme.install` route that uses the newer theme install modal
- requires backing controller for query param support despite no template being rendered
- uses the `change-theme` controller's official theme list to fetch theme details based on query param `ref`
- added `settings.change-theme` route that lives on the old `/settings/theme/install` path and redirects to the new install route
- commented out the old theme settings routes ready for full cleanup/removal
