Installing on the Frame restarted Steam to add the shortcuts, which also closed FramePort running there.
Settings -> Installing gets a Steam library mode: now (as before; restarts also wait while FramePort runs on
the Frame), later (no restart: Steam's next start re-applies and verifies the shortcuts through bounded
steam.service hooks) or off (no shortcuts; Play starts the game from FramePort). Restart Steam now bypasses
the holds and asks before ending a running game. Agent v99.
Based on the feature branch's two commits (a311498, cf05ce2), merged onto main.