[WIP] Generate spam summary emails

[zackkatz]

Resolves #18

[what-the-diff[bot]]

PR Summary

• New Form Settings Option Added a new setting to the form settings page.
• Global Addon Settings for Spam Report Email Added global addon settings for spam report email frequency, entry limit, subject line, and message body. Users can customize these settings as needed.
• Email Templating Tags Introduced basic templating tags for the email subject line and message body, allowing users to include custom information in their reports (e.g., site name, total spam count, settings URL). The report email also provides a breakdown of spam count per form.