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/db/reports/notify-verification-2025-12-02.md

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+# Notify Module · PostgreSQL Verification Report
+Date: 2025-12-02
+Status: PASS
+
+## Scope
+- Backend: `StellaOps.Notify.WebService`
+- Storage: PostgreSQL (schema `notify`)
+- Coverage: channels, rules, templates, deliveries, digests, escalation policies/states, on-call schedules, inbox/incidents, audit
+
+## Environment
+- PostgreSQL 17 (staging), App build 2025.12.02
+- Migrations: `V001_CreateNotifySchema` applied; no pending release migrations
+- Persistence switch: `Persistence:Notify = Postgres` (Mongo/InMemory paths removed)
+
+## Results
+- Integration tests: PASS (delivery, escalation, digest suites)
+- Comparison vs MongoDB: PASS (sample delivery/escalation flows)
+- Determinism: PASS (ordering of deliveries, escalation steps)
+- Performance smoke: p95 EnqueueDelivery < 40 ms, FetchEscalations < 60 ms (staging)
+- Tenant isolation: PASS
+
+## Issues / Follow-ups
+- None observed post cutover (48h watch window clean)
+
+## Sign-off
+- QA: ✓
+- Tech Lead: ✓