feat: security policy

.github/security.md

@@ -0,0 +1,3 @@
+## Reporting a Vulnerability
+If you are positive you found a vulnerability, please contact me through a direct message by [joining my Discord server](https://dc.sv443.net/) or via E-Mail ([address is on my homepage](https://sv443.net)).  
+Please don't open a GitHub issue or discussion thread.