Twitch chat relay. Embed this page in an iframe and postMessage {type: 'join', channels: ['somechannel', ...]} to it; it replies with {type: 'status', state} and {type: 'lines', lines} messages containing raw Twitch IRC lines, plus periodic {type: 'stream', channel, uptime, viewers, title} status from decapi and {type: 'emotes', channel, ...} sets per channel. {type: 'auth', token} logs the socket in as that user, after which {type: 'send', channel, text} posts to a joined channel; the relay replies {type: 'auth', login} or an error. {type: 'streamprobe', channels: [...]} asks for a one-shot decapi status check on channels outside the join set, answered with the same {type: 'stream'} reports.