docs: Update example

example/omemo_dart_example.dart

@@ -145,6 +145,11 @@ void main() async {
       /// The text of the <payload /> element, if it exists. If not, then the message might be
       /// a hearbeat, where no payload is sent. In that case, use null.
       payload,
+
+      /// Since we did not receive this message due to a catch-up mechanism, like MAM, we
+      /// set this to false. If we, however, did use a catch-up mechanism, we must set this
+      /// to true to prevent the OPKs from being replaced.
+      false,
     ),
   );
 

lib/src/omemo/omemo.dart

@@ -394,7 +394,7 @@ class OmemoManager {
     } else {
       // Check if we even have a ratchet
       if (!_ratchetMap.containsKey(ratchetKey)) {
-        // TODO: Check if we recently failed to build a session with the device
+        // TODO(Unknown): Check if we recently failed to build a session with the device
         // This causes omemo_dart to build a session with the device.
         if (!_deviceList[stanza.bareSenderJid]!
             .contains(stanza.senderDeviceId)) {
@@ -517,7 +517,7 @@ class OmemoManager {
           bundle,
           ownDevice.ik,
         );
-        // TODO: Track the failure and do not attempt to encrypt to this device
+        // TODO(Unknown): Track the failure and do not attempt to encrypt to this device
         //                on every send.
         if (kexResultRaw.isType<InvalidKeyExchangeSignatureError>()) {
           encryptionErrors.appendOrCreate(