Spring Boot Microservices

Use Micrometer Tracing with the OpenTelemetry bridge rather than creating trace IDs manually. Add the tracing and metrics dependencies, for example `micrometer-tracing-bridge-otel`, configure the exporter/propagation in `application.yaml`, and ensure the context travels through HTTP clients, message handlers, and `@Async` execution.

Every log line should carry the trace/span correlation fields. Use SLF4J and structured JSON logging in production; if you add request metadata to MDC, clear it in a `finally` block so pooled threads cannot leak one request's context into another. Configure log correlation for the service and propagate the trace context through Feign/HTTP Interfaces and Spring Cloud Stream messages.

Expose metrics and tracing diagnostics through Actuator, but secure `/actuator/**` and expose only the endpoints needed by operators. Verify the implementation by making a request across at least two services, checking that the same trace is visible in both services and that the trace ID appears in logs. Also test async and failure paths, where missing propagation is common.