decomposer: generate deliverable files for Define the service contract and project architecture for the FastAPI endpoint monitoring service.; Implement the typed monitor CRUD API and concurrency-safe in-memory state according to the service design.; Implement secure on-demand endpoint checks with status updates, latency measurement, robust error handling, and redacted structured logs.; Add operational API endpoints and environment-driven runtime configuration to the monitoring service.; Create automated tests for the monitoring service.; Package the service with Docker and developer documentation.; Validate the complete project.

VALIDATION.md

@@ -0,0 +1,16 @@
+# Validation handoff
+
+The executable validation contract is `scripts/validate.sh`, covering Ruff lint, Ruff formatting, strict mypy, and pytest. Tests provide concrete assertions for CRUD, status transitions, error envelopes, concurrent store access, timeout mapping, query redaction, private DNS answers, and redirect revalidation.
+
+The repository-generation interface used to create this revision did not expose a shell or Docker daemon, so no honest local command transcript can be supplied from that interface. Accordingly, test, static-check, image-build, startup, and smoke-test results are **not claimed as executed here**. Run:
+
+```sh
+python -m pip install -e '.[dev]'
+./scripts/validate.sh
+docker build -t endpoint-monitor .
+docker run --rm -d --name endpoint-monitor -p 8000:8000 endpoint-monitor
+curl -fsS http://127.0.0.1:8000/healthz
+docker rm -f endpoint-monitor
+```
+
+Persist CI output alongside this file when available. Operational limitation: all resources and statuses disappear on restart and diverge if more than one process or replica is used.