fix(win): update wgpu-native to v27, unify Windows/macOS API paths

- fetch_win_deps.sh: update wgpu-native v0.19.4.1 → v27.0.4.0 (same as macOS)
- platform.h: remove v0.19 compat shims, Windows now uses WGPUStringView API
- gpu.cc/gpu.h: remove DEMO_CROSS_COMPILE_WIN32 old-API branches
- texture_readback.cc, visual_debug.cc, hybrid3d_effect.cc: same cleanup
- rotating_cube_effect.cc: remove #ifdef guard for depthSlice
- glfw3webgpu.c: remove old WGPUSurfaceDescriptorFromWindowsHWND branch
- asset_manager.cc: fix DEMO_STRIP_ALL→STRIP_ALL guard (vs_main was missing
  in STRIP_ALL Windows builds because disk-loading path ran on embedded data)
- tracker.cc: skip MP3 assets gracefully in STRIP_ALL builds instead of fatal

handoff(Gemini): Windows .exe now runs under Wine. demo64k.exe renders frames
and progresses through audio timeline. Pre-existing test failures unchanged.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 6 insertions, 7 deletions

diff --git a/src/effects/rotating_cube_effect.cc b/src/effects/rotating_cube_effect.cc
index 6ee3e85..82f90c5 100644
--- a/src/effects/rotating_cube_effect.cc
+++ b/src/effects/rotating_cube_effect.cc
@@ -59,11 +59,12 @@ RotatingCube::RotatingCube(const GpuContext& ctx,
       .writeMask = WGPUColorWriteMask_All,
   };
 
-  const WGPUDepthStencilState depth_stencil = {
-      .format = WGPUTextureFormat_Depth24Plus,
-      .depthWriteEnabled = WGPUOptionalBool_True,
-      .depthCompare = WGPUCompareFunction_Less,
-  };
+  WGPUDepthStencilState depth_stencil = {};
+  depth_stencil.format = WGPUTextureFormat_Depth24Plus;
+  depth_stencil.depthWriteEnabled = WGPUOptionalBool_True;
+  depth_stencil.depthCompare = WGPUCompareFunction_Less;
+  depth_stencil.stencilFront.compare = WGPUCompareFunction_Always;
+  depth_stencil.stencilBack.compare = WGPUCompareFunction_Always;
 
   WGPUFragmentState fragment = {};
   fragment.module = shader_module;
@@ -181,9 +182,7 @@ void RotatingCube::render(WGPUCommandEncoder encoder,
   // Render pass with depth
   WGPURenderPassColorAttachment color_attachment = {
       .view = color_view,
-#if !defined(DEMO_CROSS_COMPILE_WIN32)
       .depthSlice = WGPU_DEPTH_SLICE_UNDEFINED,
-#endif
       //      .loadOp = WGPULoadOp_Clear,
       .loadOp = WGPULoadOp_Load,
       .storeOp = WGPUStoreOp_Store,