Initial commit — DeckShift v0.1.0

Steam Deck-style gaming mode for Linux + Hyprland. Lineage:
Super-Shift-S-Omarchy-Deck-Mode → Omarchy Deck → DeckShift (renamed for
distro-portability — distro-agnostic features on the roadmap).

Currently targets Omarchy (Arch + Hyprland + SDDM + iwd). Includes:

- Press Super+Shift+S to enter Gaming Mode (Gamescope + Steam Big
  Picture), Super+Shift+R to return to desktop
- NVIDIA GSP-aware driver branch selection (legacy nvidia-580xx-utils
  for Maxwell/Pascal/Volta cards)
- AMD support (vulkan-radeon, libvdpau)
- Intel support (vulkan-intel, intel-media-driver) with generation-aware
  performance warning before continuing
- Idempotent package installs via Omarchy's omarchy-pkg-add
- Optional Xbox Bluetooth controller support (xpadneo-dkms)
- Settings TUI launched from Walker (deckshift-settings) for adjusting
  monitor / GPU / resolution / refresh rate after install:
  * Buffered changes — explicit Save and exit / Cancel
  * hyprctl-based mode detection with monitor-capability filtering
  * Save-time warning if values exceed monitor capability
  * Esc returns to main menu without crashing
- Multilib check removed (Omarchy ships with multilib enabled)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

applications/deckshift-settings.desktop

@@ -0,0 +1,12 @@
+[Desktop Entry]
+Version=1.0
+Type=Application
+Name=DeckShift Settings
+GenericName=Gaming Mode Settings
+Comment=Adjust monitor, GPU, resolution, and refresh rate for DeckShift Gaming Mode
+Exec=xdg-terminal-exec --app-id=TUI.float -e deckshift-settings
+Icon=input-gaming
+Terminal=false
+StartupNotify=true
+Categories=Settings;Game;
+Keywords=gaming;steam;gamescope;deck;monitor;refresh;gpu;deckshift;