fix: fix tool-calls finish reason conversion in streaming mode for newer gemini models like gemini-3.5-flash#2399

aabchoo merged 3 commits into

envoyproxy:mainenvoyproxy/ai-gateway:mainfrom

hustxiayang:fix-gemini-3.5-streaming-finish-reasonhustxiayang/ai-gateway:fix-gemini-3.5-streaming-finish-reasonCopy head branch name to clipboard