更新MD文件路径引用

- 修正主README.md中的所有路径引用，使其与当前文件结构一致
- 更新翁凯C语言学习指南链接路径
- 更新五子棋AI项目文档链接路径
- 更新数据结构学习文档链接路径
- 修正编译说明和学习模块使用指南中的目录路径
- 改进五子棋README.md的编译运行说明，增加Windows和Linux/macOS的分平台指导
- 确保所有文档链接和路径引用都能正确工作

数据结构/课上代码练习/开课前作业/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2025 LHY
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.