gaming: add Steam/Sunshine stack + user-space toolkit
Host (hosts/common/features/gaming/):
- move steam.nix under gaming/, add gamemode + gamescope (capSysNice)
- sunshine.nix: Sunshine stream host for Moonlight/Nvidia Shield
(openFirewall, capSysAdmin for Wayland/KMS capture, autoStart)
Home (home/common/programs/gaming.nix):
- reusable custom.gaming module: Lutris, Heroic, ProtonPlus,
protontricks, MangoHud, vkbasalt, vulkan-tools
- NVIDIA-specific extras isolated behind custom.gaming.nvidia
Wire konishi: host imports ../gaming; home enables custom.gaming
with nvidia = true.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Miguel Palhas
7fff73e776