Improve Event Review flow

[Ardnived]

• Add event confirmation receipt - "Thanks for confirming. Did you actually want to edit?"
• Change the email to restate the question, and emphasise the choice between "Confirm" or "Edit"
• People need to be able to confirm without viewing the edit page.
• After you've confirmed, there should be a "view event on map" link. In the receipt or in whatsapp

[Ardnived]

Here's what the verification receipt looks like on mobile

And here's an updated version of the verification email