Add PWA support with install banner and app icons

- Configure @vite-pwa/nuxt module with manifest and service worker
- Add PWA install banner component to login page
- Include app icons (192x192, 512x512) and favicon assets
- Update admin dashboard layout and remove backup section
- Add PWA-related API endpoints and utility scripts

scripts/generate-pwa-icons.cjs

@@ -0,0 +1,64 @@
+const sharp = require('sharp');
+const fs = require('fs');
+const path = require('path');
+
+async function generatePWAIcons() {
+  const inputFile = path.join(__dirname, '../public/MONACOUSA-Flags_376x376.png');
+  const publicDir = path.join(__dirname, '../public');
+  
+  console.log('🎨 Generating PWA icons from MonacoUSA logo...');
+  
+  try {
+    // Generate 192x192 icon
+    await sharp(inputFile)
+      .resize(192, 192, { 
+        fit: 'contain',
+        background: { r: 255, g: 255, b: 255, alpha: 0 }
+      })
+      .png()
+      .toFile(path.join(publicDir, 'icon-192x192.png'));
+    
+    console.log('✅ Generated icon-192x192.png');
+    
+    // Generate 512x512 icon
+    await sharp(inputFile)
+      .resize(512, 512, { 
+        fit: 'contain',
+        background: { r: 255, g: 255, b: 255, alpha: 0 }
+      })
+      .png()
+      .toFile(path.join(publicDir, 'icon-512x512.png'));
+    
+    console.log('✅ Generated icon-512x512.png');
+    
+    // Generate Apple touch icon (180x180)
+    await sharp(inputFile)
+      .resize(180, 180, { 
+        fit: 'contain',
+        background: { r: 255, g: 255, b: 255, alpha: 1 }
+      })
+      .png()
+      .toFile(path.join(publicDir, 'apple-touch-icon.png'));
+    
+    console.log('✅ Generated apple-touch-icon.png');
+    
+    // Generate favicon (32x32)
+    await sharp(inputFile)
+      .resize(32, 32, { 
+        fit: 'contain',
+        background: { r: 255, g: 255, b: 255, alpha: 0 }
+      })
+      .png()
+      .toFile(path.join(publicDir, 'favicon-32x32.png'));
+    
+    console.log('✅ Generated favicon-32x32.png');
+    
+    console.log('🎉 All PWA icons generated successfully!');
+    
+  } catch (error) {
+    console.error('❌ Error generating PWA icons:', error);
+    process.exit(1);
+  }
+}
+
+generatePWAIcons();