Allows to turn on the Grounding with Google Search switch since the beginning, when page finish loading, to avoid doing more clicks (interactions) when the user already wants to enable that feature for a specific prompt.
as an example could be grounding=true query parameter on https://aistudio.google.com/app/prompts/new_chat?model=gemini-2.5-pro-exp-03-25&grounding=true
This only makes sense for the models which have that feature like gemini-2.5-pro-exp-03-25 and gemini-2.0-flash-001 (for now)