Implement InMemory Transport Layer for StellaOps Router

- Added InMemoryTransportOptions class for configuration settings including timeouts and latency.
- Developed InMemoryTransportServer class to handle connections, frame processing, and event management.
- Created ServiceCollectionExtensions for easy registration of InMemory transport services.
- Established project structure and dependencies for InMemory transport library.
- Implemented comprehensive unit tests for endpoint discovery, connection management, request/response flow, and streaming capabilities.
- Ensured proper handling of cancellation, heartbeat, and hello frames within the transport layer.

docs/modules/authority/gaps/SHA256SUMS

@@ -0,0 +1,2 @@
+# Hash index for authority gap artefacts (AU1–AU10, RR1–RR10)
+# Append lines: "<sha256>  <relative-path>"