Add system monitoring with real-time metrics to admin dashboard

- Add systeminformation package for system metrics collection
- Create system-metrics utility for CPU, memory, disk monitoring
- Update admin stats API to return real system health data
- Replace mock data with live system metrics in admin dashboard
- Update @vite-pwa/nuxt to v0.10.8

server/api/admin/stats.get.ts

@@ -17,15 +17,38 @@ export default defineEventHandler(async (event) => {
     
     console.log('✅ Admin access verified for user:', session.user.email);
     
-    // For now, return improved mock data - TODO: integrate with real data sources
+    // Get real system metrics
+    const { getSystemMetrics, getSystemHealthStatus, formatBytes } = await import('~/server/utils/system-metrics');
+    const systemMetrics = await getSystemMetrics();
+    const systemHealth = getSystemHealthStatus(systemMetrics);
+    
+    // Build comprehensive stats with real data
     const stats = {
+      // Real system metrics
       totalUsers: 156, // TODO: Get from Keycloak API
-      activeUsers: 45, // TODO: Get from session store
+      activeUsers: 45, // TODO: Get from session store  
       totalSessions: 67, // TODO: Get from session store
-      systemHealth: 'healthy',
+      systemHealth,
       lastBackup: new Date().toISOString(),
-      diskUsage: '45%',
-      memoryUsage: '62%',
+      diskUsage: `${systemMetrics.disk.usagePercent}%`,
+      memoryUsage: `${systemMetrics.memory.usagePercent}%`,
+      
+      // Enhanced system metrics with real data
+      systemMetrics: {
+        cpu: systemMetrics.cpu.usage,
+        memory: systemMetrics.memory.usagePercent,
+        disk: systemMetrics.disk.usagePercent,
+        uptime: systemMetrics.uptime,
+        processes: systemMetrics.processes.total,
+        cpuCores: systemMetrics.cpu.cores,
+        cpuModel: systemMetrics.cpu.model,
+        memoryTotal: formatBytes(systemMetrics.memory.total),
+        memoryUsed: formatBytes(systemMetrics.memory.used),
+        diskTotal: formatBytes(systemMetrics.disk.total),
+        diskUsed: formatBytes(systemMetrics.disk.used)
+      },
+      
+      // Mock data for features not yet implemented
       recentActivity: [
         { 
           action: 'User login', 
@@ -46,12 +69,7 @@ export default defineEventHandler(async (event) => {
           type: 'success'
         }
       ],
-      systemMetrics: {
-        cpu: 45,
-        memory: 62,
-        disk: 38,
-        uptime: '5d 12h 30m'
-      },
+      
       securityAlerts: [
         {
           id: 1,
@@ -70,7 +88,7 @@ export default defineEventHandler(async (event) => {
       ]
     };
     
-    console.log('✅ Admin stats retrieved successfully');
+    console.log('✅ Admin stats retrieved successfully with real system metrics');
     return stats;
     
   } catch (error: any) {