feat: redesign admin settings with tree navigation and compact layout

- Replace flat sidebar with collapsible tree groups (7 groups, 52 sub-items)
- Map all 61 backend category keys to sidebar navigation
- Add QuickToggles panel for boolean settings
- Replace card-style SettingRow with compact SettingsTableRow
- Add breadcrumb navigation for tree sub-items
- Add source badges (modified/DB/ENV) on settings
- Implement two-level mobile navigation with group chips
- Add i18n translations for all new keys (en, ru, zh, fa)

src/locales/zh.json

@@ -1535,6 +1535,7 @@
       "title": "系统设置",
       "allCategories": "所有分类",
       "noSettings": "未找到设置",
+      "quickToggles": "快速开关",
       "modified": "已修改",
       "readOnly": "只读",
       "reset": "重置",
@@ -1609,6 +1610,86 @@
       "quickPresets": "快速预设",
       "resetAllColors": "重置所有颜色",
       "statusColors": "状态颜色",
+      "favorites": "收藏",
+      "branding": "品牌",
+      "theme": "主题",
+      "payments": "支付",
+      "subscriptions": "订阅",
+      "interface": "界面",
+      "notifications": "通知",
+      "database": "数据库",
+      "system": "系统",
+      "users": "用户",
+      "customization": "自定义",
+      "settingsLabel": "设置",
+      "backToAdmin": "返回管理面板",
+      "totalCount": "共 {{count}} 项",
+      "modifiedCount": "已修改 {{count}} 项",
+      "badgeDb": "数据库",
+      "badgeEnv": "环境变量",
+      "groups": {
+        "payments": "支付",
+        "subscriptions": "订阅",
+        "interface": "界面",
+        "users": "用户",
+        "notifications": "通知",
+        "database": "数据库",
+        "system": "系统"
+      },
+      "tree": {
+        "payments_general": "通用",
+        "payments_stars": "Telegram Stars",
+        "payments_yookassa": "YooKassa",
+        "payments_cryptobot": "CryptoBot",
+        "payments_cloudpayments": "CloudPayments",
+        "payments_freekassa": "FreeKassa",
+        "payments_kassa_ai": "Kassa AI",
+        "payments_platega": "Platega",
+        "payments_pal24": "PAL24",
+        "payments_heleket": "Heleket",
+        "payments_mulenpay": "MulenPay",
+        "payments_tribute": "Tribute",
+        "payments_wata": "Wata",
+        "payments_riopay": "RioPay",
+        "payments_severpay": "SeverPay",
+        "subs_core": "核心",
+        "subs_trial": "试用",
+        "subs_pricing": "定价",
+        "subs_periods": "周期",
+        "subs_traffic": "流量",
+        "subs_simple": "简单订阅",
+        "subs_autopay": "自动支付",
+        "iface_general": "通用",
+        "iface_connect": "连接按钮",
+        "iface_miniapp": "MiniApp",
+        "iface_happ": "HAPP",
+        "iface_widget": "登录小部件",
+        "iface_oidc": "OIDC",
+        "iface_skip": "跳过步骤",
+        "iface_additional": "附加",
+        "users_support": "支持",
+        "users_referral": "推荐",
+        "users_channel": "频道",
+        "users_localization": "本地化",
+        "users_moderation": "审核",
+        "notif_user": "用户通知",
+        "notif_admin": "管理员通知",
+        "notif_reports": "报告",
+        "db_general": "通用",
+        "db_postgres": "PostgreSQL",
+        "db_sqlite": "SQLite",
+        "db_redis": "Redis",
+        "sys_core": "核心与调试",
+        "sys_remnawave": "RemnaWave",
+        "sys_webapi": "Web API",
+        "sys_webhook": "Webhook",
+        "sys_server": "服务器状态",
+        "sys_monitoring": "监控",
+        "sys_maintenance": "维护",
+        "sys_backup": "备份",
+        "sys_version": "版本",
+        "sys_logging": "日志"
+      },
       "categories": {
         "TELEGRAM_WIDGET": "Telegram Login Widget",
         "TELEGRAM_OIDC": "Telegram Login (OIDC)"