voice: add response_format to ModelSettings and chat()#4559

vishal-seshagiri-infinitusai wants to merge 2 commits intolivekit:mainlivekit/agents:mainfrom

vishal-seshagiri-infinitusai:vishal_feature_issue_4558vishal-seshagiri-infinitusai/agents:vishal_feature_issue_4558Copy head branch name to clipboard