feat: add PWA support with vite-plugin-pwa

Install vite-plugin-pwa with Workbox service worker generation for offline
caching, app installability, and auto-update support. Moves manifest generation
into Vite config as the single source of truth, adds a ReloadPrompt component
for update notifications, and configures runtime caching strategies for app
chunks (CacheFirst), S3 music audio (NetworkFirst), and analytics (NetworkOnly).

https://claude.ai/code/session_018fBAoG5EAjCW1AMAGTmUyh

Author: claude

index.html

@@ -26,7 +26,7 @@
     <link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png" />
     <link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png" />
     <link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
-    <link rel="manifest" href="/site.webmanifest" />
+
 
     <!-- Open Graph / Facebook / Discord / iMessage -->
     <meta property="og:type" content="website" />