FEATURE: Chat group captcha

[fet1sov]

Description

Create captcha system for the chat group join event. It helps filtering the spam bots and other bad activity.

List of functionality requirements

• Describe event chatjoin.event.ts
  • Generate picture with 6-digits
  • Delete all user messages if they not equals the captcha message
  • Wait until user will send the code from picture
  • Remember user in table with confimed account if it sent correct code