feat(python): add zeroclaw-tools companion package for LangGraph tool calling

- Add Python package with LangGraph-based agent for consistent tool calling
- Provides reliable tool execution for providers with inconsistent native support
- Includes tools: shell, file_read, file_write, web_search, http_request, memory
- Discord bot integration included
- CLI tool for quick interactions
- Works with any OpenAI-compatible provider (Z.AI, OpenRouter, Groq, etc.)

Why: Some LLM providers (e.g., GLM-5/Zhipu) have inconsistent tool calling behavior.
LangGraph's structured approach guarantees reliable tool execution across all providers.

python/zeroclaw_tools/tools/base.py

@@ -0,0 +1,46 @@
+"""
+Base utilities for creating tools.
+"""
+
+from typing import Any, Callable, Optional
+
+from langchain_core.tools import tool as langchain_tool
+
+
+def tool(
+    func: Optional[Callable] = None,
+    *,
+    name: Optional[str] = None,
+    description: Optional[str] = None,
+) -> Any:
+    """
+    Decorator to create a LangChain tool from a function.
+
+    This is a convenience wrapper around langchain_core.tools.tool that
+    provides a simpler interface for ZeroClaw users.
+
+    Args:
+        func: The function to wrap (when used without parentheses)
+        name: Optional custom name for the tool
+        description: Optional custom description
+
+    Returns:
+        A BaseTool instance
+
+    Example:
+        ```python
+        from zeroclaw_tools import tool
+
+        @tool
+        def my_tool(query: str) -> str:
+            \"\"\"Description of what this tool does.\"\"\"
+            return f"Result: {query}"
+        ```
+    """
+    if func is not None:
+        return langchain_tool(func)
+
+    def decorator(f: Callable) -> Any:
+        return langchain_tool(f, name=name)
+
+    return decorator