feat: transform Freshers-Hub into installable Progressive Web App (PWA) with offline caching

vite.config.ts

@@ -1,6 +1,7 @@
 import { defineConfig } from 'vite'
 import react from '@vitejs/plugin-react'
 import tailwindcss from '@tailwindcss/vite'
+import { VitePWA } from 'vite-plugin-pwa'
 import path from 'path'
 
 // https://vite.dev/config/
@@ -8,6 +9,43 @@ export default defineConfig({
   plugins: [
     react(),
     tailwindcss(),
+    VitePWA({
+      registerType: 'autoUpdate',
+      includeAssets: ['favicon.ico', 'apple-touch-icon.png', 'map.png'],
+      manifest: {
+        name: 'RIT Freshers Hub',
+        short_name: 'Freshers Hub',
+        description: 'Your all-in-one AI-powered student portal for Rajalakshmi Institute of Technology.',
+        theme_color: '#F97316',
+        background_color: '#FAFAFA',
+        display: 'standalone',
+        orientation: 'portrait',
+        scope: '/',
+        start_url: '/',
+        icons: [
+          {
+            src: 'pwa-192x192.png',
+            sizes: '192x192',
+            type: 'image/png'
+          },
+          {
+            src: 'pwa-512x512.png',
+            sizes: '512x512',
+            type: 'image/png'
+          },
+          {
+            src: 'pwa-maskable-512x512.png',
+            sizes: '512x512',
+            type: 'image/png',
+            purpose: 'maskable'
+          }
+        ]
+      },
+      workbox: {
+        globPatterns: ['**/*.{js,css,html,ico,png,svg,webp,webm}'],
+        maximumFileSizeToCacheInBytes: 10 * 1024 * 1024
+      }
+    })
   ],
   server: {
     host: true,