Please package https://invent.kde.org/plasma/plasma-login-manager It shouldn't replace SDDM by default (yet), but it would be good to allow users doing that for testing purposes
will do
now packaged in unstable edition - https://build.neon.kde.org/view/3%20noble%20unstable%20%E2%98%A3%20git%20master/view/noble%20unstable%20%E2%98%A3%20neon-packaging/job/noble_unstable_neon-packaging_plasma-login-manager/