feat: add node/status filters, custom date range, connected devices to traffic page

- Add NodeFilter dropdown with flag emojis and checkbox selection
- Add StatusFilter dropdown with colored status dots
- Add DateRangePicker with From/To date inputs, toggle from period mode
- Devices column now shows N/M (connected/limit) with accent color
- Export CSV passes all active filters to backend
- New i18n keys for nodes, statuses, dates in ru/en/zh/fa

src/locales/en.json

@@ -804,7 +804,18 @@
       "loading": "Loading traffic data...",
       "noTariff": "\u2014",
       "search": "Search by name or username",
-      "allTariffs": "All tariffs"
+      "allTariffs": "All tariffs",
+      "nodes": "Nodes",
+      "allNodes": "All nodes",
+      "status": "Status",
+      "allStatuses": "All",
+      "statusActive": "Active",
+      "statusTrial": "Trial",
+      "statusExpired": "Expired",
+      "statusDisabled": "Disabled",
+      "customDates": "Dates",
+      "dateFrom": "From",
+      "dateTo": "To"
     },
     "emailTemplates": {
       "title": "Email Templates",

src/locales/fa.json

@@ -685,7 +685,18 @@
       "loading": "در حال بارگذاری داده‌های ترافیک...",
       "noTariff": "\u2014",
       "search": "جستجو بر اساس نام یا نام کاربری",
-      "allTariffs": "همه تعرفه‌ها"
+      "allTariffs": "همه تعرفه‌ها",
+      "nodes": "نودها",
+      "allNodes": "همه نودها",
+      "status": "وضعیت",
+      "allStatuses": "همه",
+      "statusActive": "فعال",
+      "statusTrial": "آزمایشی",
+      "statusExpired": "منقضی",
+      "statusDisabled": "غیرفعال",
+      "customDates": "تاریخ",
+      "dateFrom": "از",
+      "dateTo": "تا"
     },
     "emailTemplates": {
       "title": "قالب‌های ایمیل",

src/locales/ru.json

@@ -825,7 +825,18 @@
       "loading": "Загрузка данных о трафике...",
       "noTariff": "\u2014",
       "search": "Поиск по имени или юзернейму",
-      "allTariffs": "Все тарифы"
+      "allTariffs": "Все тарифы",
+      "nodes": "Ноды",
+      "allNodes": "Все ноды",
+      "status": "Статус",
+      "allStatuses": "Все",
+      "statusActive": "Активная",
+      "statusTrial": "Пробная",
+      "statusExpired": "Истекла",
+      "statusDisabled": "Отключена",
+      "customDates": "Даты",
+      "dateFrom": "От",
+      "dateTo": "До"
     },
     "emailTemplates": {
       "title": "Email-шаблоны",

src/locales/zh.json

@@ -685,7 +685,18 @@
       "loading": "正在加载流量数据...",
       "noTariff": "\u2014",
       "search": "按名称或用户名搜索",
-      "allTariffs": "所有套餐"
+      "allTariffs": "所有套餐",
+      "nodes": "节点",
+      "allNodes": "所有节点",
+      "status": "状态",
+      "allStatuses": "全部",
+      "statusActive": "活跃",
+      "statusTrial": "试用",
+      "statusExpired": "已过期",
+      "statusDisabled": "已禁用",
+      "customDates": "日期",
+      "dateFrom": "从",
+      "dateTo": "到"
     },
     "paymentMethods": {
       "title": "支付方法",