refactor(web): migrate frontend to Tailwind CSS and Vike SSR

- Replace Mantine UI components with Tailwind CSS v4
- Migrate from static HTML to Vike-based SSR framework
- Disable SSR for game page (Emscripten requires browser environment)
- Simplify Emscripten loading to avoid hydration conflicts
- Remove Tailwind download logic from web.build.ts
- Add package manager lockfiles for reproducible builds
- Update .gitignore for node_modules and build artifacts

web/layouts/tailwind.css

@@ -1 +1,29 @@
 @import "tailwindcss";
+
+@layer base {
+  :root {
+    font-family:
+      "Nunito",
+      ui-sans-serif,
+      system-ui,
+      -apple-system,
+      "Segoe UI",
+      Roboto,
+      "Helvetica Neue",
+      Arial,
+      "Noto Sans",
+      "Apple Color Emoji",
+      "Segoe UI Emoji",
+      "Segoe UI Symbol",
+      sans-serif;
+  }
+
+  h1,
+  h2,
+  h3,
+  h4,
+  h5,
+  h6 {
+    font-weight: 800;
+  }
+}