Bug | Replace timing-based ready message hack with deterministic handshake

[AnnaSasDev]

Severity

High (major feature broken)

Describe the bug

Window-created registration currently depends on Task.Delay(1000), which is timing fragile.

Steps to reproduce

1. Launch app on slow or loaded machine.
2. Observe intermittent missed or delayed registration behavior.

Expected behavior

Ready flow should be deterministic and acknowledgement-based.

Actual behavior

Behavior depends on timing window.

Logs / Error Output

Intermittent missing registration behavior.

Minimal reproduction

Stress startup and inspect message registration order.

.NET Version

No response

Project Version / Commit

No response

Operating System

No response

Checklist

• I searched existing issues
• I can reproduce this consistently
• I included logs and/or a reproduction