Add instructions for debugging email issues

[ArendPeter]

Overview

There should be a message above the "send" button before the admin sends their email blasts. This will give them a 101 for debugging email errors.

Action Items

Above the send button, insert plaintext with the following message

"Not seeing emails if your inbox? First make sure to check spam. If that doesn't work please use the feedback widget in the corner and team member will work with you promptly"

This will also may need to be expanded to a helper to explain the various email error messages from #713 , this could also be linked to from the message as an additional step before submitting feedback

Resources/Instructions

No response

I have set labels for the following more labels info

• Role
• Complexity

[masiarek]

Opened #1533 — the note goes above the Send button, using your copy verbatim, and lives in en.yaml as emails.delivery_note so a writer can edit it without touching code.

Left out the second half deliberately: expanding this into a helper that explains the individual email error messages from #713 needs those messages catalogued first, and is a bigger job than a line above a button. Worth its own issue if you want it.