feat(tests): Add test_mesh tool for OBJ loading and normal visualization

Implemented a new standalone test tool 'test_mesh' to:
- Load a .obj file specified via command line.
- Display the mesh with rotation and basic lighting on a tiled floor.
- Provide a '--debug' option to visualize vertex normals as cyan lines.
- Updated asset_packer to auto-generate smooth normals for OBJs if missing.
- Fixed various WGPU API usage inconsistencies and build issues on macOS.
- Exposed Renderer3D::GetVisualDebug() for test access.
- Added custom Vec3 struct and math utilities for OBJ parsing.
This tool helps verify mesh ingestion and normal computation independently of the main demo logic.

1 files changed, 5 insertions, 1 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8e79ba4..ff47cea 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -375,6 +375,10 @@ if(DEMO_BUILD_TESTS)
     add_demo_executable(test_3d_physics src/tests/test_3d_physics.cc ${PLATFORM_SOURCES} ${GENERATED_TIMELINE_CC} ${GEN_DEMO_CC} ${GENERATED_MUSIC_DATA_CC})
     target_link_libraries(test_3d_physics PRIVATE 3d gpu audio procedural util ${DEMO_LIBS})
     add_dependencies(test_3d_physics generate_timeline generate_demo_assets generate_tracker_music)
+
+    add_demo_executable(test_mesh src/tests/test_mesh.cc ${PLATFORM_SOURCES} ${GENERATED_TIMELINE_CC} ${GEN_DEMO_CC} ${GENERATED_MUSIC_DATA_CC})
+    target_link_libraries(test_mesh PRIVATE 3d gpu audio procedural util ${DEMO_LIBS})
+    add_dependencies(test_mesh generate_timeline generate_demo_assets generate_tracker_music)
 endif()
 
 #-- - Extra Tools -- - 
@@ -398,4 +402,4 @@ add_custom_target(final
 add_custom_target(pack_source
     COMMAND tar -czf demo_all.tgz --exclude=.git --exclude=build* --exclude=.gemini* --exclude=*.tgz --exclude=*.zip --exclude=.DS_Store .
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-)
+)
\ No newline at end of file