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/core/filewriter/constructor.md

@@ -0,0 +1,81 @@
+# FileWriter::FileWriter
+
+## 重载 1: 默认构造
+
+```cpp
+FileWriter();
+```
+
+默认构造 FileWriter 对象，不打开任何文件。
+
+**描述**
+
+创建 FileWriter 实例，m_file 初始化为 nullptr。可后续通过 Open 方法打开文件。
+
+**参数：** 无
+
+**返回：** 无
+
+**线程安全：** ❌
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include <XCEngine/Core/FileWriter.h>
+
+using namespace XCEngine::Core;
+
+FileWriter writer;
+if (!writer.IsOpen()) {
+    writer.Open("output.txt");
+    writer.Write("Hello\n");
+    writer.Close();
+}
+```
+
+---
+
+## 重载 2: 文件路径构造
+
+```cpp
+FileWriter(const char* filePath, bool append = false);
+```
+
+构造 FileWriter 对象并打开文件。
+
+**参数：**
+- `filePath` - 要打开的文件路径
+- `append` - 是否以追加模式打开，默认 false（覆盖模式）
+
+**返回：** 无
+
+**线程安全：** ❌
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include <XCEngine/Core/FileWriter.h>
+
+using namespace XCEngine::Core;
+
+// 覆盖模式打开
+FileWriter writer1("output.txt");
+if (writer1.IsOpen()) {
+    writer1.Write("Content\n");
+}
+
+// 追加模式打开
+FileWriter writer2("log.txt", true);
+if (writer2.IsOpen()) {
+    writer2.Write("New log entry\n");
+}
+```
+
+## 相关文档
+
+- [FileWriter 总览](filewriter.md) - 返回类总览
+- [Open](Open.md) - 打开文件