xLightsSequencer/xLights ? reverse-engineered prompt

I want to get xLights building and running on my machine, and I’d like you to fix whatever is needed so I can open the app, create light sequences, make playlists, and test hardware from the UI.

Please follow the existing Linux build notes in the repo, use the current source as the starting point, and make sure the project builds cleanly with a normal local setup. If anything is missing or outdated, update it so the build is as straightforward as possible. If you need to check current docs or tool versions online, go ahead.

Once it builds, please make sure the app launches without obvious errors and that the main features mentioned in the README are available, especially sequencing, playlists, scheduling, hardware testing, and sequence conversion. If you run into any build issues from dependencies or platform setup, fix them in the repo so the next person can build it more easily.