feat: add a quick reply workflow using the Ctrl+Up arrow key

neochat now supports a quick reply shortcut, which helps to reply to
the last event in a room.

imports/NeoChat/Component/ChatBox/ChatBox.qml

@@ -18,6 +18,7 @@ Item {
     signal fancyEffectsReasonFound(string fancyEffect)
     signal messageSent()
     signal editLastUserMessage()
+    signal replyPreviousUserMessage()
 
     Kirigami.Theme.colorSet: Kirigami.Theme.View
 
@@ -157,6 +158,9 @@ Item {
         onEditLastUserMessage: {
             root.editLastUserMessage();
         }
+        onReplyPreviousUserMessage: {
+            root.replyPreviousUserMessage();
+        }
     }
 
     function checkForFancyEffectsReason() {