server: scrub a departed user's pending invites via a User.invited reverse index instead of scanning every channel on the network per quit — the old O(channels)-per-quit path was O(channels*quits) on a netsplit; the index is maintained at the 4 invite add/remove sites (INVITE cmd, S2S INVITE, join-consume, UNINVITE)

src/modules/reputation.rs

@@ -392,6 +392,7 @@ mod tests {
                 caps: Caps::default(),
                 sasl_mech: None,
                 channels: chans,
+                invited: crate::map::HashSet::default(),
                 watch: Vec::new(),
                 monitor: Vec::new(),
                 silence: Vec::new(),