[multimodal] Let Audio take float data blob

[pytorchbot]

If the processed audio went through Mel transform, the spectrogram are float values. We should allow Audio class to be able to take this, since multimodal runner pybind API will have to be able to take processed input. Once we have the pybind API we can do something like:

model_id = "mistralai/Voxtral-Mini-3B-2507"
processor = AutoProcessor.from_pretrained(model_id)
audio_url = "https://huggingface.co/datasets/eustlb/audio-samples/resolve/main/dude_where_is_my_car.wav"
conversation = [
    {
        "role": "user",
        "content": [
            {"type": "audio", "url": audio_url},
            {
                "type": "text",
                "text": "What can you tell me about this audio?",
            },
        ],
    },
]
inputs = processor.apply_chat_template(conversation,
    tokenize=True,
    return_dict=True,
    return_tensors="pt")

inputs_combined = [
    make_text_input("<s>[INST][BEGIN_AUDIO]"),
    make_audio_input(inputs["input_features"]),
    make_text_input("\nWhat can you tell me about this audio?[/INST]"),
]
runner = MultimodalRunner("voxtral.pte", "tekken.json", None)
config = GenerationConfig()
config.max_new_tokens = 100
runner.generate(inputs_combined, config)

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[pytorch-bot]

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❌ 2 New Failures, 1 Cancelled Job

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• pull / unittest-buck / macos / macos-job (gh)
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