dev/core#5587, dev/core#5560 - backport 31455 - restore validation of emails in profiles

[demeritcowboy]

Overview

Backport #31455

[civibot]

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[civibot]

The issue associated with the Pull Request can be viewed at https://lab.civicrm.org/dev/core/-/issues/5587

[totten]

Spot-checked some use-cases for the backport. Seems fine.