Fix retention query performance and cleanup scheduling

src/lib/server/pipeline/worker.ts

@@ -21,6 +21,7 @@ import { trackActivity } from './activity.js';
 import { withOperationSource } from '../hosts/operation-context.js';
 
 const TICK_MS = 15_000;
+const RETENTION_INTERVAL_MS = 5 * 60_000;
 // Match each agent's two health lanes without making unrelated hosts wait.
 const STATUS_CONCURRENCY_PER_HOST = 2;
 
@@ -31,6 +32,7 @@ let statusTimer: NodeJS.Timeout | null = null;
 let tickInFlight: Promise<void> | null = null;
 let tickRequested = false;
 const requesterFlights = new Map<string, Promise<void>>();
+let nextRetentionAt = 0;
 
 function tick(requestAnother = false): Promise<void> {
     if (requestAnother) tickRequested = true;
@@ -57,6 +59,10 @@ function reconcileRequesters(): void {
     ];
     for (const [key, label, work] of requesters) {
         if (requesterFlights.has(key)) continue;
+        if (key === 'retention') {
+            if (Date.now() < nextRetentionAt) continue;
+            nextRetentionAt = Date.now() + RETENTION_INTERVAL_MS;
+        }
         const flight = trackActivity(key, label, work)
             .catch(err => { console.error(`[worker] ${key} error:`, err); })
             .then(async () => { if (key !== 'game-files' && key !== 'retention') await tick(true); })