webchathelper: add interaction duration into js argument

Change-Id: I28b8ac1f8d158db3a86bd21a0e325d1db893aa70

src/webchathelpers.cpp

@@ -38,6 +38,7 @@ buildInteractionJson(lrc::api::ConversationModel& conversationModel,
     interactionObject.insert("sender_contact_method", QJsonValue(sender));
     interactionObject.insert("timestamp", QJsonValue(timestamp));
     interactionObject.insert("direction", QJsonValue(direction));
+    interactionObject.insert("duration", QJsonValue(interaction.duration));
 
     switch (interaction.type)
     {