feat(home): package Claude Desktop and T3 Code, with per-host UI scaling

Add two Electron AI desktop apps built from their official upstream
binaries and wire them into the home config (x86_64 only):

- claude-desktop: Anthropic's official Linux .deb, unpacked via dpkg +
  autoPatchelfHook. Wrapper disables the SUID sandbox (nix store can't
  set it up) and adds the NixOS GL driver path so it hardware-accelerates
  instead of falling back to software rendering.
- t3-code: pingdotgg/t3code AppImage via appimageTools.wrapType2, with
  desktop entry + hicolor icons.

Both share a new custom.aiApps.deviceScaleFactor option feeding
--force-device-scale-factor; konishi's 4K@1x monitors set it to "1.5",
arrakis stays native.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

home/common/programs/dev.nix

@@ -5,6 +5,7 @@
 {
   imports = [
     ./ralph-claude-code.nix
+    ./t3-code.nix
   ];
 
   programs = {