Lack of Security file

[coderbm1]

Hello,
It would be great to see Security.md file https://github.com/HabitRPG/habitica/security I think. (with at least some contact to the proper Team)

Kind regards,

[M-ayank2005]

Hello,

I would like to adding a SECURITY.md file to this repository. If you could provide the appropriate contact details, I’d be happy to create and add this file to enhance our security practices.

Thank you!