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/tests/test_tools.py

@@ -0,0 +1,62 @@
+"""
+Tests for zeroclaw-tools package.
+"""
+
+import pytest
+
+
+def test_import_main():
+    """Test that main package imports work."""
+    from zeroclaw_tools import create_agent, shell, file_read, file_write
+
+    assert callable(create_agent)
+    assert hasattr(shell, "invoke")
+    assert hasattr(file_read, "invoke")
+    assert hasattr(file_write, "invoke")
+
+
+def test_import_tool_decorator():
+    """Test that tool decorator works."""
+    from zeroclaw_tools import tool
+
+    @tool
+    def test_func(x: str) -> str:
+        """Test tool."""
+        return x
+
+    assert hasattr(test_func, "invoke")
+
+
+def test_agent_creation():
+    """Test that agent can be created with default tools."""
+    from zeroclaw_tools import create_agent, shell, file_read, file_write
+
+    agent = create_agent(
+        tools=[shell, file_read, file_write], model="test-model", api_key="test-key"
+    )
+
+    assert agent is not None
+    assert agent.model == "test-model"
+
+
+@pytest.mark.asyncio
+async def test_shell_tool():
+    """Test shell tool execution."""
+    from zeroclaw_tools import shell
+
+    result = await shell.ainvoke({"command": "echo hello"})
+    assert "hello" in result
+
+
+@pytest.mark.asyncio
+async def test_file_tools(tmp_path):
+    """Test file read/write tools."""
+    from zeroclaw_tools import file_read, file_write
+
+    test_file = tmp_path / "test.txt"
+
+    write_result = await file_write.ainvoke({"path": str(test_file), "content": "Hello, World!"})
+    assert "Successfully" in write_result
+
+    read_result = await file_read.ainvoke({"path": str(test_file)})
+    assert "Hello, World!" in read_result