Function parse_approval_route 

pub fn parse_approval_route(route: &str) -> Option<(&str, &str)>

Parse a channel_key:recipient route into its two non-empty halves. Splits on the FIRST : only, so a recipient that itself contains : (e.g. a Matrix @user:server id) survives intact on the right. Channel-map keys are dot-separated (discord.ops), never colon-separated, so the first colon is unambiguously the channel/recipient boundary.