Fix auth issues

[Rinary1]

Fixes bug with alternative auth:

1. Client tries to use discord even if it's unsupported, fixed by adding "wantDiscord" field into encryption, which will be false if it's unsupported or disabled on this server. So client will use default auth.
2. AuthMode changed enum values cause this:

SS14.Launcher.Models.Connector+ConnectException: Failed to connect: ConnectionFailed
 ---> System.Text.Json.JsonException: The JSON value could not be converted to SS14.Launcher.Models.AuthMode. Path: $.auth.mode | LineNumber: 0 | BytePositionInLine: 54.