refactor(#2077): drop impl-history from broker/dashboard/mcp comments

hive-c0re/src/broker.rs

@@ -1260,8 +1260,8 @@ mod tests {
     }
 
     /// Convenience wrapper for tests that want single-pop semantics
-    /// — the broker only exposes `recv_batch` publicly now, so
-    /// every test that used to call `recv` goes through here.
+    /// — the broker only exposes `recv_batch` publicly, so tests
+    /// funnel single pops through here.
     fn pop_one(broker: &Broker, recipient: &str) -> Option<Delivery> {
         let mut batch = broker.recv_batch(recipient, 1).unwrap();
         batch.pop()