feat(ai): simpler In-Memory-Ratelimiter pro IP

src/lib/server/ai/rate-limit.ts

@@ -0,0 +1,21 @@
+export type RateLimiter = { check: (key: string) => boolean };
+
+export function createRateLimiter(opts: {
+  windowMs: number;
+  max: number;
+}): RateLimiter {
+  const store = new Map<string, { count: number; resetAt: number }>();
+  return {
+    check(key: string): boolean {
+      const now = Date.now();
+      const entry = store.get(key);
+      if (!entry || entry.resetAt <= now) {
+        store.set(key, { count: 1, resetAt: now + opts.windowMs });
+        return true;
+      }
+      if (entry.count >= opts.max) return false;
+      entry.count += 1;
+      return true;
+    }
+  };
+}