fix: reduce mutation auto-flush threshold from 5 to 2

Lower the auto-flush threshold for workflow mutations from 5 to 2 to ensure
more timely data persistence. Since mutations are less frequent than regular
telemetry events, a lower threshold provides:

- Faster data persistence (don't wait for 5 mutations)
- Better testing experience (easier to verify with fewer operations)
- Reduced risk of data loss if process exits before threshold
- More responsive telemetry for low-volume mutation scenarios

This complements the existing 5-second periodic flush and process exit
handlers, ensuring mutations are persisted promptly.

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

src/telemetry/telemetry-manager.ts

@@ -166,9 +166,10 @@ export class TelemetryManager {
         // Queue for batch processing
         this.eventTracker.enqueueMutation(mutationRecord);
 
-        // Auto-flush if queue is large
+        // Auto-flush if queue reaches threshold
+        // Lower threshold (2) for mutations since they're less frequent than regular events
         const queueSize = this.eventTracker.getMutationQueueSize();
-        if (queueSize >= 5) { // Flush after 5 mutations
+        if (queueSize >= 2) {
           await this.flushMutations();
         }
       }