feat(observability): instrument all micro-services

[pmcfadin]

Goal / Acceptance criteria:\n\nInstrument every dedicated service entry-point (app/main_.py) with configure_observability(app) so that traces, metrics and Loki logs are emitted just like the monolith.\n\n• Call configure_observability() immediately after creating the FastAPI instance.\n• Ensure Prometheus /metrics route isn’t duplicated.\n• Add missing opentelemetry / prometheus deps to pyproject.\n• Update .env.example with minimal OTEL_ variables.\n• Unit test starts each service under test settings and asserts Instrumentator metrics route exists.\n\nContext: Prompt 2025-07-07 – Python Observability Guide discussion.

[pmcfadin]

⏳

[pmcfadin]

✅ Micro-service entrypoints now attach Configure_observability; env.example updated. All tests pass. Continuing to monitor.

[pmcfadin]

✅ Done. All micro-services instrumented, env.example updated, and tests added to ensure Prometheus /metrics route.