feat(web): scaffold SvelteKit SPA with Tailwind + adapter-static

- SvelteKit 2.x + Svelte 5 + TypeScript + Vite 5
- adapter-static with fallback:'index.html' for SPA deep-link routing
- Tailwind configured with dark-only palette matching spec
- Placeholder landing page at /
- Committed web/build/index.html placeholder (via .gitignore negation) so
  go:embed works before the SvelteKit build has been run

web/tsconfig.json

@@ -0,0 +1,14 @@
+{
+  "extends": "./.svelte-kit/tsconfig.json",
+  "compilerOptions": {
+    "allowJs": true,
+    "checkJs": true,
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "skipLibCheck": true,
+    "sourceMap": true,
+    "strict": true,
+    "moduleResolution": "bundler"
+  }
+}