The versions page shows each node's update state with update buttons, API
tokens get a release scope that can only register releases (used by CI), and
the CI image and release builds now pass the tag, commit and build time.
Squash of recent dev work: return_session login, backend switcher, line
detail timeline, overview strips, node platform/country/ISP info with flags
and icons, build info (version, tag, time) behind site.show_build, and the
acrylic display theme.