Add Missing Date and Message-ID Headers to Ensure Email Delivery (Fix #4066)

[ThomaciousD]

Summary

This PR fixes the issue where emails sent through send_email() were not being delivered due to missing required headers. Adding the Date and Message-ID headers ensures proper email metadata, preventing certain email providers (e.g., Gmail) from rejecting or discarding emails.

Fix Implemented

Imported formatdate and make_msgid from email.utils
Added:

msg["Date"] = formatdate(localtime=True)
msg["Message-ID"] = make_msgid()

to ensure emails have the required headers.

Related Issue

Closes #4066

Testing

✅ Verified emails are now delivered correctly.
✅ Checked SMTP debug logs (set_debuglevel(1)) and confirmed correct email metadata.
✅ Ensured emails arrive in both inbox and spam folder across different email providers.

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