feat(editor): F4.6a simulation mode and a computer's desktop

Java's mode buttons start and stop the room, now in a worker of the
editor's page (LocalSimHost), with Java's speed slider. While the
simulation runs the design is locked as in Java: no palette, no sheet,
nothing moves, no undo. Cables that carry a frame light up in Java's
green, and a tap on a computer opens its desktop: Java's title, the
software installation first, then the installed programs in the order
of Java's list for the language, a taskbar with the network icon and
the network as the simulation runs it. The room sends that over a new
topic, node:<id>. Desktops stay over a return to the design and show
again at the next start. The programs' windows follow from F4.6b.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/editor/src/i18n/i18n.tsx

@@ -24,6 +24,10 @@ export function LanguageProvider({ language, children }: { readonly language: La
   return <LanguageContext.Provider value={language}>{children}</LanguageContext.Provider>;
 }
 
+export function useLanguage(): Language {
+  return useContext(LanguageContext);
+}
+
 export function useTranslate(): Translate {
   const language = useContext(LanguageContext);
   return (key, values) => translate(language, key, values);