Expose the Wayland socket to the sandbox, and enable Wayland at build time using the new ENABLE_WAYLAND define for CMake.
The Chromium sandbox is conflicting with the Flatpak sandbox in a non-trivial, non-workaroundable way. Until Chromium / CEF provides a way to unconditionally disable the entire sandbox, let's not degrade the Flatpak experience.
Add a new com.obsproject.Studio.json file containing the dependencies and permissions required by OBS Studio. RFC: https://github.com/obsproject/rfcs/pull/21