add channel for checkin process

app/channels/checkin_channel.rb

@@ -0,0 +1,10 @@
+class CheckinChannel < ApplicationCable::Channel
+  def subscribed
+    stream_from "checkin_channel"
+  end
+
+  def unsubscribed
+  	stop_all_streams
+    # Any cleanup needed when channel is unsubscribed
+  end
+end