refactor: improve test infrastructure and fix OpenGL GLAD initialization

- Rename D3D12Enum.h to D3D12Enums.h for naming consistency
- Fix OpenGL unit test GLAD initialization by using gladLoadGL()
  instead of gladLoadGLLoader(wglGetProcAddress) for fallback support
- Migrate remaining tests to use gtest_discover_tests for granular
  test discovery (math, core, containers, memory, threading, debug,
  components, scene, resources, input, opengl)
- Remove obsolete TEST_RESOURCES_DIR and copy_directory commands
  from OpenGL unit test CMakeLists (minimal/Res doesn't exist)
- Update TEST_SPEC.md with performance metrics and per-module
  build/test commands for faster development workflow
- Update CMake path references to use lowercase paths

docs/api/threading/task-system-config/max-task-queue-size.md

@@ -0,0 +1,24 @@
+# TaskSystemConfig::maxTaskQueueSize
+
+```cpp
+uint32_t maxTaskQueueSize = 1024
+```
+
+任务队列的最大容量。当队列满时，新提交的任务将阻塞直到有空间。
+
+**类型：** `uint32_t`
+
+**默认值：** `1024`
+
+**当前状态：** 此配置项当前未实际强制限制，任务队列可以无限增长（受系统内存限制）。
+
+**示例：**
+
+```cpp
+TaskSystemConfig config;
+config.maxTaskQueueSize = 4096; // 预留配置项（当前未强制限制）
+```
+
+## 相关文档
+
+- [TaskSystemConfig 总览](tasksystemconfig.md) - 返回类总览