invitationview: sort per received timestamp

We sort the invites by last interactions. However on swarm, there
is no interaction yet. Add one with the received timestamp given
by the daemon.
(Regression appears because we were showing trust request before
not conversation requests)

Change-Id: Ic7f4d1a5d485325c95a19c2c38ae9c74630829ce
GitLab: #956

src/libclient/conversationmodel.cpp

@@ -3063,6 +3063,17 @@ ConversationModelPimpl::addConversationRequest(const MapStringString& convReques
     conversation.mode = mode;
     conversation.isRequest = true;
 
+    MapStringString messageMap = {
+        {"type", "initial"},
+        {"author", peerUri},
+        {"timestamp", convRequest["received"]},
+        {"linearizedParent", ""},
+    };
+    auto msg = interaction::Info(messageMap, linked.owner.profileInfo.uri);
+
+    insertSwarmInteraction(convId, msg, conversation, true);
+    conversation.lastMessageUid = convId;
+
     // add the author to the contact model's contact list as a PENDING
     // if they aren't already a contact
     auto isSelf = linked.owner.profileInfo.uri == peerUri;