Inhibit idle for fullscreen Steam games (steam_app_*), not just the Steam client — screensaver fires mid-game on controller input

[RandomJerk]

Summary

default/hypr/apps/steam.lua inhibits idle for the Steam client (class = "steam", i.e. Big Picture) but not for the games themselves, which run as steam_app_<appid>. A fullscreen game played on a controller looks completely idle to Hyprland — gamepad input goes straight to the game via Steam Input/SDL and never passes through the compositor — so idle.screensaver fires over the match after 150 s, and idle.lock after 300 s.

Suggest adding one rule next to the existing one:

-- Games run as steam_app_<appid>. Gamepad input never reaches the compositor,
-- so a fullscreen game on a controller looks idle and the screensaver fires mid-game.
o.window({ class = "^steam_app_.*$" }, { idle_inhibit = "fullscreen" })

Why this and not something else

• Steam's own screensaver inhibit and gamemode's inhibit_screensaver use the org.freedesktop.ScreenSaver D-Bus interface, which Hyprland doesn't implement, so neither helps on Omarchy.
• Scoped to fullscreen deliberately: a windowed or alt-tabbed game lets idle behave normally.
• Omarchy's idle service already honours inhibitors (respectInhibitors: true in shell/plugins/services/idle/Service.qml), so nothing else needs to change.
• The full-match pattern matters: Hyprland matches rule regexes against the whole class, so ^steam_app_ alone never matches steam_app_3468650. The existing steam rule works because it's the complete class.

Verified

Omarchy 4.0.3-1, Hyprland 0.56.2, NVIDIA 610.57.04. Added the rule to ~/.config/hypr/hyprland.lua, relaunched a Proton/XWayland game, polled hyprctl -j clients:

23:13:35  steam_app_3468650  fullscreen=0  inhibitingIdle=False   (window mapped)
23:13:37  steam_app_3468650  fullscreen=2  inhibitingIdle=True    (fullscreen -> inhibitor on)
23:30:19  (game closed)

Seventeen minutes on controller only, no screensaver. Before the rule, the same session produced the screensaver at 150 s with inhibitingIdle=False.

Happy to open a PR if that's preferred.