fix: 修复 NameError/状态污染/类型标注/统计; 补全练习与 main; 新增 config/.gitignore/requirements; 文档统一

step_05_07_advanced/main.py

@@ -0,0 +1,17 @@
+"""
+Step 05-07: RAG / Self-Correction / Multi-Agent 主程序
+
+运行方式：
+    cd step_05_07_advanced
+    python main.py
+"""
+
+from concept import demo
+
+
+def main():
+    demo()
+
+
+if __name__ == "__main__":
+    main()