Support customizable (and shorter) delay for Communication Emails.

Right now the "Communication Emails" notification option can be used to get email notifications about missed messages. However it appears that these are only sent after 24h of inactivity. However a lot can happen in 24h and that is a long time to keep some messages waiting. It would be great if this can be customized. For example 1h would be great for being more interactive and 7w may be good for people who just occasionally want to check in. Even an "Immediate" option may be useful for those who don't want to miss anything.

For example other chat apps support much quicker notifications: