FunctionTool raises TypeError for positional-only parameters after successful schema validation #8319

FunctionTool builds a valid argument schema for an annotated Python function with positional-only parameters, but run_json() passes those parameters as keywords and raises TypeError.

import asyncio
from autogen_core import CancellationToken
from autogen_core.tools import FunctionTool

def scale(value: int, /, *, factor: int = 2) -> int:
    return value * factor

async def main() -> None:
    tool = FunctionTool(scale, description="Scale a value.")
    print(tool.schema)
    print(await tool.run_json({"value": 3}, CancellationToken()))

asyncio.run(main())

Expected result: 6. Actual result: TypeError: scale() got some positional-only arguments passed as keyword arguments: 'value'.

The same problem affects async functions and functions whose cancellation_token is positional-only. It occurs after argument validation, in FunctionTool.run.

Reproduced on main at 027ecf0a379bcc1d09956d46d12d44a3ad9cee14 (autogen-core 0.7.5), Windows, Python 3.12.2. Eight regression cases fail on the unchanged implementation, covering sync/async execution, positional defaults, partial, and cancellation-token injection. No model credentials or network calls are involved.