feat: complete v0.5 operations foundation

lib/rate-limit.ts

@@ -1,8 +1,19 @@
-const visits = new Map<string, { count: number; resetAt: number }>();
+import { db } from "@/lib/db";
 
-export function withinRateLimit(key: string, limit = 30, windowMs = 60_000) {
-  const now = Date.now(); const record = visits.get(key);
-  if (!record || record.resetAt <= now) { visits.set(key, { count: 1, resetAt: now + windowMs }); return true; }
-  if (record.count >= limit) return false;
-  record.count += 1; return true;
+/** SQLite-backed fixed-window limiter shared by every Web container using this database. */
+export function withinRateLimit(bucket: string, limit = 30, windowMs = 60_000) {
+  const now = Date.now();
+  const transaction = db.transaction(() => {
+    const found = db.prepare("SELECT count,reset_at FROM rate_limits WHERE bucket=?").get(bucket) as { count: number; reset_at: number } | undefined;
+    if (!found || found.reset_at <= now) {
+      db.prepare("INSERT INTO rate_limits(bucket,count,reset_at) VALUES(?,?,?) ON CONFLICT(bucket) DO UPDATE SET count=excluded.count,reset_at=excluded.reset_at").run(bucket, 1, now + windowMs);
+      return true;
+    }
+    if (found.count >= limit) return false;
+    db.prepare("UPDATE rate_limits SET count=count+1 WHERE bucket=?").run(bucket);
+    return true;
+  });
+  const allowed = transaction();
+  if (Math.random() < 0.01) db.prepare("DELETE FROM rate_limits WHERE reset_at<?").run(now);
+  return allowed;
 }