Add Steam Provider

[Revadike]

This is my attempt at adding a Steam provider. I do not know go very well. I also have not tested this, as I am new to supabase.

[Makosai]

@cstockton What sort of work is needed here?

I'd personally like to see an easier way to add custom auth systems as a developer. Steam is one of the platforms I'd like to use but I'd also like to use GOG, Epic Games, and a few other platforms.

I'm sure, outside of the gaming sector, there are people who might want other platforms too. So what about a customizable auto system?

I'm more than happy to contribute here with some guidance.

[Revadike]

@cstockton What sort of work is needed here?

I'd personally like to see an easier way to add custom auth systems as a developer. Steam is one of the platforms I'd like to use but I'd also like to use GOG, Epic Games, and a few other platforms.

I'm sure, outside of the gaming sector, there are people who might want other platforms too. So what about a customizable auto system?

I'm more than happy to contribute here with some guidance.

Currently, I use an edge function that does the openid check for Steam and if passed, use generate magiclink to get a login token that I send back to the user. This works, but it still requires an email... I just use <steamid>@steam as email for now. I am not sure how safe this is.