Add localization for active players and most popular labels in English and Chinese

src/App.tsx

@@ -255,7 +255,7 @@ function App() {
                   padding: '0.5rem 0',
                   borderBottom: '1px solid var(--border-color)'
                 }}>
-                  <span style={{ color: 'var(--text-secondary)' }}>Active Players</span>
+                  <span style={{ color: 'var(--text-secondary)' }}>{t('activity.activePlayers')}</span>
                   <span style={{ 
                     color: 'var(--accent-primary)',
                     fontWeight: 'bold'
@@ -269,7 +269,7 @@ function App() {
                   alignItems: 'center',
                   padding: '0.5rem 0'
                 }}>
-                  <span style={{ color: 'var(--text-secondary)' }}>Most Popular</span>
+                  <span style={{ color: 'var(--text-secondary)' }}>{t('activity.mostPopular')}</span>
                   <span style={{ 
                     color: 'var(--text-primary)',
                     fontWeight: 'bold',

src/locales/en.json

@@ -61,7 +61,9 @@
     "serverInfo": "Server Info",
     "serverStatus": "Status: Online ✓",
     "currentMap": "Map: de_dust2",
-    "nextRestart": "Restart: 6h 30m"
+    "nextRestart": "Restart: 6h 30m",
+    "activePlayers": "Active Players",
+    "mostPopular": "Most Popular"
   },
   "footer": {
     "community": "🎯 CS Community",

src/locales/zh.json

@@ -60,7 +60,9 @@
     "serverInfo": "服务器信息",
     "serverStatus": "状态：在线 ✓",
     "currentMap": "地图：de_dust2",
-    "nextRestart": "重启：6小时30分钟"
+    "nextRestart": "重启：6小时30分钟",
+    "activePlayers": "活跃玩家",
+    "mostPopular": "最热门"
   },
   "footer": {
     "community": "🎯 CS 社区",