seo: implement OpenAPI operation rendering and add llms documentation

apps/wiki/app/openapi.json/route.ts

@@ -0,0 +1,16 @@
+import {openapi} from '@/lib/openapi';
+
+export const revalidate = false;
+
+export async function GET() {
+  const schemas = await openapi.getSchemas();
+  const first = Object.values(schemas)[0];
+  if (!first) return new Response('Not found', {status: 404});
+
+  return new Response(JSON.stringify(first.bundled), {
+    headers: {
+      'Content-Type': 'application/json; charset=utf-8',
+      'Cache-Control': 'public, max-age=300, s-maxage=3600',
+    },
+  });
+}