[V1] Enable multi-input by default

[DarkLight1337]

This PR enables multiple multi-modal input items for V1 without having to set limit_mm_per_prompt.

Note: This may increase the default memory usage for multi-modal models because max_num_mm_items_decoder_budget no longer limits max_num_mm_items in GPUModelRunner.profile_run. You can explicitly set the limit to one via limit_mm_per_prompt or even disable unused modalities completely by setting the limit of that modality to zero. I have added a section to the Offline Inference docs accordingly.

There is no need to set limits for V1 since encoder and decoder are profiled separately which should avoid OOM during inference time. The only hard limit is the context length which is checked in Processor._validate_model_inputs already.

Note: Users can still limit_mm_per_prompt to exclude individual modalities from being profiled and used in inference.

This is loosely a follow-up to #15703 which removed the direct dependency of various models on multimodal limits.

Some other changes:

• To reduce memory cost, unused modalities are now fully disabled in examples and the common model tests, instead of using the default limit of that modality.
• Fix incorrect type annotations of data parsing overrides for MiniCPM-O/V and Qwen2-VL.

[github-actions]

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[Isotr0py]

Overall look reasonable to me!