[WIP] Add basic Steam Deck instructions

[AlexKlimaj]

This PR adds basic setup instructions for running QGC on the Steam Deck. I have tested basic connection, firmware upgrades, and stick functionality. Most of the normal buttons work. Buttons R4, R5, L4, and L5 don't work.

I am unable to bring up the on screen keyboard in QGC which is very annoying.

I have not tested video streaming out of the box.

[Williangalvani]

Nice!

I also experimented with the steamdeck. I ended up needing to build a flatpak image for the video streaming to work. I'll try to find the branch here and open at least a draft PR so people don't go through the same trouble again.

[AlexKlimaj]

Nice!

I also experimented with the steamdeck. I ended up needing to build a flatpak image for the video streaming to work. I'll try to find the branch here and open at least a draft PR so people don't go through the same trouble again.

That would be great. Ideally we get the flatpak build into CI.

Have you been able to bring up the on screen keyboard when QGC is open?

[hamishwillee]

I've converted to draft. Please move to ready for review when you want this looked at/merged.

[hamishwillee]

I migrated docs to https://github.com/mavlink/qgroundcontrol/tree/master/docs/en

If this is still valid, can you copy the PR across? I will be archiving this in a week or so.