Keyboard(remote) not working with rdp when rdp is secondary backend and shell=kiosk

There is new multi-backend mode in weston 13.0.

I trying to test nested KDE with RDP screen sharing. When using RDP+wayland backends with shell kiosk(needed to run nested compositor) there is warning in log "WARNING: multiple seats detected. kiosk-shell can not handle multiple seats!" and keyboard in remote RDP sesiion not working.

After inspecting weston code I found problem source - rdp backend always create new seat for incoming connection, and kiosk-shell not supporting multiple seats now.

But I should note: when using a shared screen, it is a common thing to use a shared keyboard and mouse (seat).

I wrote "quick&dirty" fix for that. Fix attached. Also attached script to run nested kde in podman container to test poroblem.

0001-Unconditionally-share-seat-when-rdp-is-secondary-bac.patch run_neon.sh