Add vpinball: a browser Visual Pinball player

Next.js app that plays real .vpx tables via @valknar/vpinball-wasm
(WebAssembly Visual Pinball). Demo mode with the bundled default
table, drag-and-drop custom table upload, a cabinet-styled UI with a
coin-door HUD (fullscreen/stats/info/eject), a custom 404 page, PWA
support (hand-rolled service worker), and a static Docker Compose
deployment behind nginx.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012hQoM3jJT1Lx7CMTciMzvD

app/manifest.ts

@@ -0,0 +1,28 @@
+import type { MetadataRoute } from "next";
+
+// Required under output: "export" — a manifest route has no per-request
+// dynamic behavior anyway, so this just makes that explicit to the build.
+export const dynamic = "force-static";
+
+export default function manifest(): MetadataRoute.Manifest {
+  return {
+    name: "vpinball — Visual Pinball in your browser",
+    short_name: "vpinball",
+    description: "Play real .vpx pinball tables in the browser, powered by WebAssembly.",
+    start_url: "/",
+    display: "fullscreen",
+    background_color: "#0b0b0f",
+    theme_color: "#0b0b0f",
+    icons: [
+      { src: "/icons/icon-192.png", sizes: "192x192", type: "image/png" },
+      { src: "/icons/icon-512.png", sizes: "512x512", type: "image/png" },
+      {
+        src: "/icons/icon-512-maskable.png",
+        sizes: "512x512",
+        type: "image/png",
+        purpose: "maskable",
+      },
+      { src: "/icons/icon.svg", sizes: "any", type: "image/svg+xml" },
+    ],
+  };
+}