Update `auth.go` to improve debugging capabilities

The auth.go file is updated to include extra logging details for password and account verification methods, and for geoIP and mail information. Additionally, the "GetAccount" method has been clarified to return an empty string if account value is not set, and the "PostLuaAction" has been updated to asynchronously execute a Lua action. These changes provide more detailed information in the debug mode to aid in troubleshooting.