v2.4.0 — internationalization (EN/RU) + custom git templates

- i18n engine (lib/i18n.sh, lib/lang/en.sh, lib/lang/ru.sh)
- first-run language picker, persisted to .language + config.json
- install.sh, common.sh, backup.sh, templates_catalog.sh wired through t()/tf()
- backup.sh preserves .language marker and records language in metadata.json
- custom git template feature (first item in pro template picker)
  * validates HTTPS URLs, rejects shell metachars
  * 100MB size guard, 90s clone timeout
  * auto-detects index.html in dist/public/build/_site/site/docs/out/www
- bot v2.4.0: i18n.py + lang/{en,ru}.json, /lang command, language toggle button
- bot: custom git template via text input with waiter gating

gotelegram-bot/bot.py

@@ -912,6 +912,9 @@ async def _download_custom_git_template(url_with_branch: str) -> Tuple[bool, str
         ):
             url = base
             branch = maybe_branch
+        elif not maybe_branch and base.lower().startswith("https://"):
+            # Trailing `@` with no branch — drop it so git doesn't treat it as userinfo
+            url = base
 
     tpl_id = "custom_" + hashlib.md5(url_with_branch.encode("utf-8")).hexdigest()[:10]
     target_dir = f"/opt/gotelegram/custom_templates/{tpl_id}"