Import SortingName from Steam appinfo

[psychonic]

It looks like this would either require reworking of the Steam plugin, or adding SortingName to the data that metadata providers can provide, but the SortingName for a game can be provided for Steam games from their app info.

Like Playnite, Steam only populates this field when sort name is meant to override the game's name for the purposes of sorting. It's in the common section, with keyname of SortAs.

If also adding support to pulling the SortingName from metadata providers, it's as simple as adding a few lines to SteamMetadataProvider.UpdateGameWithMetadata.

    if (metadata.ProductDetails["common"]["SortAs"] != KeyValue.Invalid)
    {
        game.SortingName = metadata.ProductDetails["common"]["SortAs"].Value;
    }

A full list of games with this key set (5000+) is available via SteamDB at https://steamdb.info/search/?a=app_keynames&type=-1&keyname=290&operator=4&keyvalue= (requires Steam login to use that search)