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/postcss.config.cjs

@@ -1,14 +1,3 @@
 module.exports = {
-  plugins: {
-    "postcss-preset-mantine": {},
-    "postcss-simple-vars": {
-      variables: {
-        "mantine-breakpoint-xs": "36em",
-        "mantine-breakpoint-sm": "48em",
-        "mantine-breakpoint-md": "62em",
-        "mantine-breakpoint-lg": "75em",
-        "mantine-breakpoint-xl": "88em",
-      },
-    },
-  },
+  plugins: {},
 };