Features for SteamDeck compatibility

[actuallySIG]

Greetings.

I would like to publish games for the SteamDeck certified as Verified on the compatibility ranking (see here: https://partner.steamgames.com/doc/steamdeck/compat#DeckCompatibilityChecklist). For this, it seems the extension would need to implement most of ISteamInput for controller support, as well as parts of ISteamUtils, specifically the functions related to text input via the on-screen keyboard, such as ShowGamepadTextInput(), ShowFloatingGamepadTextInput(), GetEnteredGamepadTextInput(), and GetEnteredGamepadTextLength(). Can support for these features be added in the extension?

Thank you.

[britzl]

Started working on this: #19