Initial commit: installable PWA hello world

React + TypeScript + Tailwind v4 + shadcn/ui frontend (client), Express +
better-sqlite3 backend (server) in a pnpm workspace. Includes vite-plugin-pwa
manifest, service worker, and iOS install meta tags. GET /api/hello increments a
visit counter in SQLite; backend serves the built client in production.

client/public/icon.svg

@@ -0,0 +1,7 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="1024" height="1024" viewBox="0 0 1024 1024">
+  <rect width="1024" height="1024" rx="224" fill="#0a0a0a" />
+  <path
+    d="M372 712V312h168c92 0 152 44 152 124 0 82-62 130-156 130h-66v146h-98zm98-220h64c42 0 64-20 64-56 0-36-22-54-64-54h-64v110z"
+    fill="#fafafa"
+  />
+</svg>