remove swap from dhtlog

lib/chat/cubits/reconciliation/message_integrity.dart

@@ -47,6 +47,11 @@ class MessageIntegrity {
     message.signature = signature.toProto();
   }
 
+  // XXX: change bool to an enum to allow for reconciling deleted
+  // XXX: messages. if a message is deleted it will not verify, but its
+  // XXX: signature will still be in place for the message chain.
+  // XXX: it should be added to a list to check for a ControlDelete that
+  // XXX: appears later in the message log.
   Future<bool> verifyMessage(proto.Message message) {
     // Ensure the message is signed
     assert(message.hasSignature(), 'should not verify unsigned message');