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",