Restore dark UI kit surfaces

Fix Vue runtime rendering in UI ...

Use Vue compiler build in Vite so runtime template components render instead of mounting an empty comment node.

Add pending document proposal form to UI

Add Git commit controls to UI

Add pending change detail and apply controls to UI

Add document drill-down to UI

Add inventory drill-down to UI

Add Vue UI scaffold with gnexus-ui-kit dependency

Add documentation foundation and backend maintenance API