FS: Setting up sockets for notifying emails being sent

[skassam21]

• In the bottom right corner, there would be a simple Alert that shows progress on how many emails have been sent when a step is being executed
• when you click the execute step button, it starts a background task to run send all emails
• as it is sending emails, it'll emit socket events to the front-end to notify the user how many emails have been sent (something like 10 / 20 etc.)