core: skip fallbacks in english translation

packages/hydrooj/src/lib/i18n.ts

@@ -7,6 +7,11 @@ declare global {
 }
 
 String.prototype.translate = function translate(...languages: string[]) {
+    if (languages[0].startsWith('en')) {
+        // For most use cases, source text equals to translated text in English.
+        // So if it doesn't exist, we should use the original text instead of fallback.
+        return locales[languages[0]]?.[this] || locales['en']?.[this] || this;
+    }
     for (const language of languages) {
         if (!language) continue;
         const curr = (locales[language] || {})[this] || (locales[language.split('_')[0]] || {})[this];