"This Page Is Not Yet Translated"

Courtesy of @smikitky

It would be cool to have a "This Page Is Not Yet Translated" component that we can stick on pages in the translation forks that haven't had a translation yet. Even though the Spanish translation is "done", some sections like the blog aren't translated, and it would be nice to give a warning like MDN does:

This would involve something like:

• A TranslationWarning component with a message on how a page isn't translated yet.
• A translated property on front matter that should be set when a page is translated
• Logic to show the translation warning if translated isn't set (and the language isn't English).

This would require a code mod for all the pages that have been already translated in the various languages, but I could probably do that with a codemod by referencing their progress list.

Inizia individuando il componente TranslationWarning proposto, la proprietà di front-matter tradotta e la logica di visualizzazione basata sulla lingua descritta nell’issue. Esamina le pagine tradotte esistenti e gli elenchi di avanzamento delle lingue prima di pianificare il codemod; il lavoro è completato quando le pagine non inglesi non tradotte mostrano l’avviso, mentre le pagine tradotte e le pagine in inglese non lo mostrano.