add search, chat, and feedback analytics with dashboard

lib/analytics/http.ts

@@ -0,0 +1,21 @@
+import 'server-only';
+import { clientKey, createRateLimiter } from '@/lib/ai/rate-limit';
+
+const checkFeedbackLimit = createRateLimiter(Number(process.env.FEEDBACK_RATE_LIMIT_PER_MINUTE ?? 60));
+
+export function json(status: number, body: object) {
+  return Response.json(body, { status });
+}
+
+/** shared guard for the feedback endpoints: rate limit + JSON body */
+export async function readFeedback(req: Request): Promise<Record<string, unknown> | Response> {
+  if (!checkFeedbackLimit(clientKey(req)).ok) return json(429, { error: 'Too many requests.' });
+  const body = (await req.json().catch(() => null)) as unknown;
+  if (!body || typeof body !== 'object') return json(400, { error: 'Invalid body.' });
+  return body as Record<string, unknown>;
+}
+
+export function storageError(scope: string, error: unknown) {
+  console.error(`[analytics] ${scope}`, error);
+  return json(503, { error: 'Feedback storage is unavailable.' });
+}