wgpu's default DX12 compiler (Auto) loads whichever dxcompiler.dll the DLL
search path finds. DeckCraft ships none, and without a matching dxil.dll the
unsigned-DXIL warning fails wgpu's indirect-validation pipeline, the device
is lost and the app exits before the first frame. Pin the compiler to FXC,
which is part of Windows; WGPU_DX12_COMPILER still overrides it.
Fixes#153
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
