docs: fix naming conventions across threading, math, memory, core, and debug modules

threading/:
- Rename 19 camelCase method files to hyphenated names
- task-system: createtaskgroup→create-task-group, etc.
- tasksystemconfig: enabletaskprofiling→enable-task-profiling, etc.
- thread: getcurrentid→get-current-id, etc.
- task: addref→add-ref, getid→get-id, etc.

math/:
- Rename underscore operator files to hyphenated
- vector3: operator_add→operator-add, etc.
- matrix4: gettranslation→get-translation, etc.
- vector4: tovector3→to-vector3, constructor_vector3→constructor-vector3
- sphere: sphere_constructor→sphere-constructor, etc.

memory/:
- Remove duplicate memorymanager/ folder (kept manager/ which was correct)

core/:
- filewriter: Consolidate ctor-default.md and ctor-file.md into constructor.md
- Rename dtor.md→destructor.md

debug/:
- filelogsink: Rename construct.md→constructor.md, ~filelogsink.md→destructor.md

All overview pages updated with new file references.

docs/api/math/vector3/operator-sub.md

@@ -0,0 +1,30 @@
+# Vector3::operator-
+
+```cpp
+Vector3 operator-(const Vector3& other) const
+```
+
+向量减法，将两个向量的对应分量相减。
+
+**参数：**
+- `other` - 要减的向量
+
+**返回：** `Vector3` - 相减结果
+
+**线程安全：** ✅
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+Vector3 a(5.0f, 7.0f, 9.0f);
+Vector3 b(1.0f, 2.0f, 3.0f);
+Vector3 c = a - b;  // (4.0f, 5.0f, 6.0f)
+```
+
+## 相关文档
+
+- [Vector3 类总览](vector3.md) - 返回类总览
+- [`operator+`](operator_add.md) - 加法运算
+- [`operator-=`](operator_sub_assign.md) - 减法赋值