feat: enhance admin user detail with campaign, panel data, node usage

- Add campaign card and referrals list to info tab
- Add panel config/links, live traffic, connection info to subscription tab
- Add node usage bars with 7/14/30 day period selector
- Add getPanelInfo/getNodeUsage API methods and types
- Add 18 new i18n keys across 4 languages

src/locales/en.json

@@ -1852,6 +1852,24 @@
         "lastActivity": "Last activity",
         "totalSpent": "Total spent",
         "purchases": "Purchases",
+        "campaign": "Advertising campaign",
+        "referralsList": "Referrals list",
+        "referralEarnings": "Referral earnings",
+        "noReferrals": "No referrals",
+        "panelConfig": "Panel configuration",
+        "trojanPassword": "Trojan password",
+        "vlessUuid": "VLESS UUID",
+        "ssPassword": "SS password",
+        "subscriptionUrl": "Subscription URL",
+        "happLink": "HAPP link",
+        "firstConnected": "First connected",
+        "lastOnline": "Last online",
+        "lastNode": "Last node",
+        "liveTraffic": "Current traffic",
+        "lifetime": "Lifetime",
+        "nodeUsage": "Node usage",
+        "copied": "Copied",
+        "panelNotFound": "User not found in panel",
         "referral": {
           "title": "Referral program",
           "referrals": "Referrals",