feat: Update BillingManager to replace 'nodeName' with 'purpose', add purpose formatting function, and enhance UI elements with consistent icon sizes

example-servers-billing.json

@@ -2,7 +2,7 @@
   {
     "id": "1",
     "hostName": "VDSINA",
-    "nodeName": "VDSINA",
+    "purpose": "relay",
     "country": "RU",
     "provider": "VDSINA",
     "loginUrl": "cp.vdsina.com",
@@ -16,7 +16,7 @@
   {
     "id": "2",
     "hostName": "Macloud",
-    "nodeName": "Macloud",
+    "purpose": "bgp",
     "country": "RU",
     "provider": "Macloud",
     "loginUrl": "cp.macloud.ru",
@@ -30,7 +30,7 @@
   {
     "id": "3",
     "hostName": "Hosting VDS",
-    "nodeName": "Steal",
+    "purpose": "monitoring",
     "country": "RU",
     "provider": "Hosting VDS",
     "loginUrl": "my.hosting-vds.com/",
@@ -44,7 +44,7 @@
   {
     "id": "4",
     "hostName": "Waicore",
-    "nodeName": "Waicore",
+    "purpose": "dns",
     "country": "DE",
     "provider": "Waicore",
     "loginUrl": "my.waicore.com/billmgr",
@@ -58,7 +58,7 @@
   {
     "id": "5",
     "hostName": "IHOR",
-    "nodeName": "Ihore",
+    "purpose": "proxy",
     "country": "RU",
     "provider": "IHOR",
     "loginUrl": "billing.ihor-hosting.ru/billmgr",