refactor: redesign spec page with clean toggle between specification and example views

- Convert to client component with useState for view toggling
- Add "Specification" view with clean schema reference and sidebar
- Add "Full Example" view with complete package.json and tool code examples
- Remove explanatory content (moved elsewhere)
- Create layout.tsx for metadata since page is client component
- Reduce page complexity from 839 to 406 lines

apps/web/src/app/spec/layout.tsx

@@ -0,0 +1,21 @@
+import type { Metadata } from 'next';
+
+export const metadata: Metadata = {
+  title: 'TPMJS Specification',
+  description:
+    'The open standard for AI tool discovery. Complete schema reference for package.json configuration.',
+  openGraph: {
+    title: 'TPMJS Specification',
+    description:
+      'The open standard for AI tool discovery. Complete schema reference for package.json configuration.',
+    images: [{ url: '/api/og/spec', width: 1200, height: 630 }],
+  },
+  twitter: {
+    card: 'summary_large_image',
+    images: ['/api/og/spec'],
+  },
+};
+
+export default function SpecLayout({ children }: { children: React.ReactNode }) {
+  return children;
+}