Localization Improvement: Use Localized Confiig Reference link for Config Reference Button

[dingyifei]

Requested feature:

The klipper-translations project has 4 additional localized Klipper documents available. Switch displayed language should also change the Config Reference and other potential links if the localized version of the document is available.

Solves the following problem:

improve localization

Additional information:

The document source is hosted on https://github.com/Klipper3d/klipper-translations where the compiled MkDocs are accessible with a link like https://www.klipper3d.org/<lang code>/<document html>.

For example, the Hungarian config reference is https://www.klipper3d.org/hu/Config_Reference.html

A full list of usable codes can be pulled from https://github.com/Klipper3d/klipper-translations/blob/translations/active_translations.

Directory Name is the regular language code following Weblate language code settings and Site Language is used in <lang code>, the rest of the entries in active_translations are for compatibility reasons.