[Feature Request] Email notification to post author when a comment is added

Request

When a comment is added to a post, please send an automatic notification email to the post author. Users should be able to know there's a reply without checking the site every time.

Notes

• SMTP is verified working (signup verification email sends OK)
• An ON/OFF toggle for notification mail in admin settings would be ideal.
• The mail body should include a post link, the commenter's name, and a preview of the comment.

Operator note (verifying): reviewing the comment notification flow. Will finalize the queue and toggle placement before moving forward.