feat: add files to tool call trace

[yzld2002]

Some tools use the files param in the send_inference_request, which cannot be captured by the ToolCallTrace

    buffer_bytes = frames_to_bytes(frames)
    files = [("video", buffer_bytes)]
    payload = {
        "prompts": [s.strip() for s in prompt.split(",")],
        "function_name": "florence2_sam2_video_tracking",
    }
    data: Dict[str, Any] = send_inference_request(
        payload, "florence2-sam2", files=files, v2=True

This PR adds the files in ToolCallTrace, which are the base64 encoded files, so we can capture the tool input files in downstream processing.