Add Firefox(Bergamot) local translation (#794)

# PR Checklist
- [ ] Have you checked if it works normally in all models? *Ignore this
if it doesn't use models.*
- [ ] Have you checked if it works normally in all web, local, and node
hosted versions? If it doesn't, have you blocked it in those versions?
- [ ] Have you added type definitions?

# Description
Translation is performed using the models hosted in the repository:
https://github.com/mozilla/firefox-translations-models/

When the translation is first running, the model is downloaded from the
repository.

Testing completed for `npm dev` and Node server environment.

src/lang/en.ts

@@ -702,6 +702,7 @@ export const languageEnglish = {
     showMenuChatList: "Show Menu Chat List",
     translatorLanguage: "Translator Language",
     translatorType: "Translator Type",
+    htmlTranslation: "HTML Translate",
     deeplKey: "deepL API Key",
     deeplFreeKey: "deepL Free API Key",
     deeplXUrl: "deepLX URL",