查询单个任务

{
    "task": {
        "id": "task_abc123",
        "model": "MiniMax-H3",
        "status": "succeeded",
        "resolution": "768P",
        "duration": 5,
        "ratio": "16:9",
        "task_type": "generation",
        "modality": "video",
        "content": {
            "url": "https://cdn.example.com/video.mp4"
        },
        "usage": {
            "total_seconds": 5,
            "input_seconds": 0,
            "output_seconds": 5,
            "input_image_count": 0,
            "input_audio_seconds": 0
        },
        "created_at": 1750000000,
        "updated_at": 1750000030
    }
}