D3D12: Add DXC availability detection and automatic FXC fallback (#2955)

* D3D12: add DXC availability detection and automatic FXC fallback

- Added DetectDXCAvailability() to validate DXC compiler and driver DXIL support
- DXC is now tested via minimal shader compilation + dummy PSO creation
- If DXC or DXIL validation fails, _dxcAvailable is disabled
- FXC fallback path is used automatically when DXC is unavailable
- Prevents PSO creation failures on OEM NVIDIA drivers (e.g. RTX 3050 series)
- Improves shader compilation robustness across Windows versions and GPU vendors

* Fix lint

* Improve code style

* Use compute shader to detect dxc availability

Author: halx99

axmol/rhi/DXUtils.cpp

@@ -178,7 +178,7 @@ DXGI_FORMAT getUAVCompatibleFormat(DXGI_FORMAT format)
 
 void fatalError(std::string_view op, HRESULT hr)
 {
-    auto msg = fmt::format("{}: 0x{:08X}", op, static_cast<unsigned>(hr));
+    auto msg = fmt::format("{}: 0x{:08x}", op, static_cast<unsigned>(hr));
 #if AX_RENDER_API == AX_RENDER_API_D3D12
     showAlert(msg, "axmol: D3D12: Fatal Error", AlertStyle::IconError | AlertStyle::RequireSync);
 #else