When a mod deletes a message flagged safe, it will be sent BE

[DecentralizedDan]

After a user flags a message as spam it goes to the Threatstream to be judged by mods, as per #112

• Once there, a mod might categorize it safe
• After that, another mod may still end up deleting it

If a mod deletes a once-flagged message, we should treat that as the same as if a mod categorized the message as spam in the first place