R1:b16db61a87f3

Allow "send me an email" in personal rules to punch through settings

Summary:
Fixes T7731. When a user writes a "Send me an email" rule, always try send them an email, even if their notification settings would normally downgrade it to a notification.

In particular, this is stronger than these downgrades:

- Downgrades due to "self actions";
- downgrades due to "mail tags".

Test Plan:
- Wrote various Herald rules with "Send me an email" rules.
- Used `bin/mail list-outbound` / `show-outbound` to…