Fix i18n: strip UTF-8 BOM so translations load again.

PowerShell rewrites had added a BOM that made Python json.load fail, so the UI showed raw keys like nav_servers.

app.py

@@ -152,7 +152,7 @@ def load_translations():
             if f.endswith('.json'):
                 lang = f.split('.')[0]
                 try:
-                    with open(os.path.join(trans_dir, f), 'r', encoding='utf-8') as tf:
+                    with open(os.path.join(trans_dir, f), 'r', encoding='utf-8-sig') as tf:
                         TRANSLATIONS[lang] = json.load(tf)
                 except Exception as e:
                     logger.error(f"Error loading translation {f}: {e}")

translations/en.json

@@ -1,4 +1,4 @@
-{
+{
     "nav_servers":  "Servers",
     "nav_users":  "Users",
     "nav_invites":  "Invite links",

translations/fa.json

@@ -1,4 +1,4 @@
-{
+{
     "nav_servers":  "سرورها",
     "nav_users":  "کاربران",
     "nav_invites":  "لینک دعوت",

translations/fr.json

@@ -1,4 +1,4 @@
-{
+{
     "nav_servers":  "Serveurs",
     "nav_users":  "Utilisateurs",
     "nav_invites":  "Liens d\u0027invitation",

translations/ru.json

@@ -1,4 +1,4 @@
-{
+{
     "nav_servers":  "Серверы",
     "nav_users":  "Пользователи",
     "nav_invites":  "Ссылки",

translations/zh.json

@@ -1,4 +1,4 @@
-{
+{
     "nav_servers":  "服务器",
     "nav_users":  "用户列表",
     "nav_invites":  "邀请链接",