Qt Wayland Compositor - Running the Wayland compositor - doc needs to update

https://doc.qt.io/qt-6/qtwaylandcompositor-index.html#running-the-wayland-compositor

About running fancy-compositor on Linux desktop,

Traditional way, on X11 session, fancy-compositor is an x11 client app, just like doc said.

But now, more and more usage with Wayland session, if like doc said, changing XDG_RUNTIME_DIR=~/my_temporary_runtime means, fancy-compositor is still an x11 client app.

But we can also just not change XDG_RUNTIME_DIR, and run fancy-compositor as a wayland client app, only setting a different --wayland-socket-name, but sharing XDG_RUNTIME_DIR with system wayland compositor.

./fancy-compositor --wayland-socket-name wayland-1

Or perhaps we need to allow fancy-compositor to have XDG_RUNTIME_DIR which talks to system wayland compositor, and set another XDG_RUNTIME_DIR which talks to its wayland clients.