Malicious link scanning

[sarge1989]

Issue

• Checkers often worried to go into links, related to Checkers need some help with accessing links in a safe manner #216
• Secondly, if site is obviously malicious, we can just mark it as scam or illicit and it does not need to trigger further flows
• To explore how best to work this into our userHandler logic when a message comes in

Task

• Identify scanning API (could be third party)
• Determine if there should be a new category for malicious links, or does current scam suffice