delayjoin +D: hide JOINs until a member speaks/reveals (NAMES + part/quit/nick aware)

src/coremods/core_channel.rs

@@ -434,7 +434,18 @@ impl Command for Part {
             } else {
                 format!(":{prefix} PART {target} :{reason}")
             };
-            s.to_channel_vis(&key, &line, uid); // +u: only ops + self see the part
+            // +D delayjoin: a still-hidden member's PART is shown only to themselves
+            let hidden = s
+                .channels
+                .get(&key)
+                .and_then(|c| c.members.get(&uid))
+                .map(|m| m.hidden)
+                .unwrap_or(false);
+            if hidden {
+                s.send(uid, line.clone());
+            } else {
+                s.to_channel_vis(&key, &line, uid); // +u: only ops + self see the part
+            }
             s.propagate_part(uid, target, &reason); // tell linked servers
             if let Some(ch) = s.channels.get_mut(&key) {
                 ch.members.remove(&uid);

src/coremods/core_message.rs

@@ -400,6 +400,8 @@ pub(crate) fn deliver(s: &mut Server, uid: Uid, params: &[String], notice: bool)
                 }
             }
         }
+        // +D delayjoin: speaking reveals a hidden member (their JOIN goes out first)
+        s.reveal_member(uid, &key);
         // deliver to every member except the sender and +D (deaf) users, tagging
         // per-recipient (server-time + any client-only tags on the line)
         let line = format!(":{prefix} {cmd} {target} :{body}");