Constant CHANNEL_SOP_SUBJECT_PREFIX 

pub const CHANNEL_SOP_SUBJECT_PREFIX: &str = "zeroclaw:sop-event:";

Reserved ChannelMessage.subject prefix the git/forge channel uses to label SOP-ingress events. Routing is NOT keyed on this (see ChannelMessage::internal_sop_event); it exists so channels that fill subject from user-controlled data (email) can keep this reserved namespace out of inbound subjects.