Multimodal support in IGW

Presently, IGW doesn't support multimodal completely. The following are the gaps:

* Support for video/audio data formats
* Support for prefix caching. The present strategy may not work based on discussion in https://www.youtube.com/watch?v=-WqJ8PbnFg8


For further investigation, refer: https://docs.google.com/document/d/1YKx31zmF-mMGgb41InQfNmaOIVlAElsUXHIgHfQe_68/edit?tab=t.0