feat(space): add thumbs-up/down feedback buttons for MTBench-Africa DPO dataset

fix(space): remove type='messages' arg incompatible with Gradio 6.0

fix(space): fix AFRICAN_LANGUAGES typo and Gradio 6.0 compatibility

feat(space): add AfriLION-branded Gradio chatbot UI with African language support

initial commit

Duplicate from gradio-templates/chatbot