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/string/reserve-resize.md

@@ -0,0 +1,51 @@
+# String::Reserve / Resize
+
+```cpp
+void Reserve(SizeType capacity);
+void Resize(SizeType newSize);
+void Resize(SizeType newSize, char fillChar);
+```
+
+管理字符串的内存和大小。
+
+**参数：**
+- `capacity` - 要预留的最小容量
+- `newSize` - 新的字符串长度
+- `fillChar` - 当扩展字符串时用于填充新增位置的字符，默认为 '\0'
+
+**返回：** 无
+
+**复杂度：**
+- `Reserve`：最坏 O(n)，仅在需要扩展容量时复制数据
+- `Resize`：O(n)，当 newSize > Length 时可能需要扩展
+
+**示例：**
+```cpp
+#include "XCEngine/Containers/String.h"
+#include <iostream>
+
+int main() {
+    XCEngine::Containers::String s("Hi");
+
+    // Reserve - 预分配内存
+    s.Reserve(100);
+    std::cout << "After Reserve(100), Capacity: " << s.Capacity() << std::endl;
+    // 输出: After Reserve(100), Capacity: 100
+
+    // Resize - 缩短字符串
+    s.Resize(1);
+    std::cout << "After Resize(1): " << s.CStr() << std::endl;  // 输出: H
+
+    // Resize - 扩展字符串，用 'X' 填充
+    s.Resize(5, 'X');
+    std::cout << "After Resize(5, 'X'): " << s.CStr() << std::endl;  // 输出: HXXXX
+
+    return 0;
+}
+```
+
+## 相关文档
+
+- [String 总览](string.md) - 返回类总览
+- [Length / Capacity](size.md) - 获取长度和容量
+- [Clear](clear.md) - 清空字符串