fix(i18n): remove duplicate subscription.servers string key

The key existed as both a string and an object in subscription
section, causing i18next to return an object instead of a string.
Removed the redundant string — serversLabel is used for plain text,
plural suffixes (_one/_few/_many/_other) handle counted usage.

src/locales/en.json

@@ -151,7 +151,6 @@
     "devices": "Devices",
     "devices_one": "{{count}} device",
     "devices_other": "{{count}} devices",
-    "servers": "Servers",
     "serversLabel": "Servers",
     "servers_one": "{{count}} server",
     "servers_other": "{{count}} servers",

src/locales/fa.json

@@ -148,7 +148,6 @@
     "extraDevicesIncluded": "شامل {{count}} دستگاه اضافی",
     "extraDevicesIncluded_other": "شامل {{count}} دستگاه اضافی",
     "baseTariff": "تعرفه",
-    "servers": "سرورها",
     "serversLabel": "سرورها",
     "servers_other": "{{count}} سرور",
     "traffic": "ترافیک",

src/locales/ru.json

@@ -165,7 +165,6 @@
     "devices_one": "{{count}} устройство",
     "devices_few": "{{count}} устройства",
     "devices_many": "{{count}} устройств",
-    "servers": "Серверы",
     "serversLabel": "Серверы",
     "servers_one": "{{count}} сервер",
     "servers_few": "{{count}} сервера",

src/locales/zh.json

@@ -148,7 +148,6 @@
     "extraDevicesIncluded": "含 {{count}} 个额外设备",
     "extraDevicesIncluded_other": "含 {{count}} 个额外设备",
     "baseTariff": "套餐",
-    "servers": "服务器",
     "serversLabel": "服务器",
     "servers_other": "{{count}} 个服务器",
     "traffic": "流量",