chore: mini-openclaw 初始版本

Next.js 前端 + FastAPI/LangChain 后端透明 agent平台
- 含 .gitignore, 敏感文件(sessions数据/.env/venv等)已排除
- 待后续添加 trajectory 自进化机制

backend/tools/python_repl_tool.py

@@ -0,0 +1,17 @@
+"""Python REPL Tool — wraps LangChain experimental PythonREPLTool."""
+
+from langchain_core.tools import BaseTool
+from langchain_experimental.tools import PythonREPLTool
+
+
+def create_python_repl_tool() -> BaseTool:
+    tool = PythonREPLTool()
+    tool.name = "python_repl"
+    tool.description = (
+        "Execute Python code in an interactive REPL environment. "
+        "Use this for calculations, data processing, running scripts, "
+        "and any task that benefits from programmatic execution. "
+        "Input should be valid Python code. "
+        "Use print() to see output."
+    )
+    return tool