MCP tools with a parameter named "config" silently broken by LangChain's RunnableConfig injection

## Bug When an MCP tool has an input parameter named `config`, `convert_mcp_tool_to_langchain_tool` produces a `StructuredTool` that silently replaces the user's `config` value with LangChain's internal `RunnableConfig` dict at invocation time. ## Reproduction ```python from mcp.types import Tool as MCPTool from langchain_mcp_adapters.tools import convert_mcp_tool_to_langchain_tool tool = MCPTool( name="my_tool", description="A tool with a config param", inputSchema={ "type": "object", "properties": { "config": {"type": "string", "description": "User config value"}, "query": {"type": "string"}, }, "required": ["config", "query"], }, ) lc_tool = convert_mcp_tool_to_langchain_tool(session, tool) # When invoked with {"config": "my_value", "query": "hello"}, # the coroutine receives config={"callbacks": ..., "tags": ..., ...} (a RunnableConfig) # instead of "my_value" ``` ## Root cause The execution path in `BaseTool.arun` ([langchain-core](https://github.com/langchain-ai/langchain/blob/master/libs/core/langchain_core/tools/base.py)): 1. `_to_args_and_kwargs` unpacks the tool input dict into `tool_kwargs` — so `tool_kwargs["config"] = "my_value"` 2. Then LangChain checks `_get_runnable_config_param(func_to_check)` against `StructuredTool._arun`, which has `config: RunnableConfig` in its signature 3. This returns `"config"`, and the code does `tool_kwargs["config"] = config` — **overwriting the user's value** with the internal `RunnableConfig` The same applies to `run_manager` and `callbacks` (via `FILTERED_ARGS`). ## Version - langchain-mcp-adapters: 0.2.2 - langchain-core: 0.3.x