fix: improve doc link navigation and tree display

- Fix link resolution with proper relative/absolute path handling
- Improve link styling with underline decoration
- Hide leaf nodes from tree, only show directories
- Fix log file path for packaged app

docs/api/containers/hashmap/operator-assign.md

@@ -0,0 +1,36 @@
+# HashMap::operator=
+
+```cpp
+HashMap& operator=(const HashMap& other);
+HashMap& operator=(HashMap&& other) noexcept;
+```
+
+赋值运算符，用另一个 HashMap 的内容替换当前内容。
+
+**参数：**
+- `other` - 源哈希表（拷贝版本为 `const` 引用，移动版本为右值引用）
+
+**返回：** 对当前对象的引用 (`*this`)
+
+**复杂度：**
+- 拷贝赋值：O(m_bucketCount + other.m_size)
+- 移动赋值：O(m_size)，需要先清空当前内容
+
+**示例：**
+
+```cpp
+XCEngine::Containers::HashMap<int, const char*> map1;
+map1.Insert(1, "one");
+map1.Insert(2, "two");
+
+XCEngine::Containers::HashMap<int, const char*> map2;
+map2 = map1; // 拷贝赋值
+
+XCEngine::Containers::HashMap<int, const char*> map3;
+map3 = std::move(map1); // 移动赋值，map1 在此调用后状态不确定
+```
+
+## 相关文档
+
+- [HashMap 总览](hashmap.md) - 返回类总览
+- [Copy/Move](copy-move.md) - 拷贝/移动构造