* Add observation to inbound endpoints
* * Improve `Observation` logic in the `MessageProducerSupport` and `MessagingGatewaySupport`
* Clean up Javadocs in observation support classes
* Add test for `MessagingGatewaySupport` instrumentation into `IntegrationObservabilityZipkinTests`
* Add docs for `@EnableIntegrationManagement.observationPatterns()`
* The generated docs for metrics and spans looks OK: have both `Gateway` and `Handler` section now
* * Fix Checkstyle violations
* * Fix `IntegrationMBeanExporter` to filter out a `MessageProducer` from sources.
Marking a `MessageProducerSupport` with an `IntegrationInboundManagement`
causes it to be considered as a source for JMX.
Technically it might have a reason since it is indeed a source, but that's fully different story
* * No observation instrumentation by default
* * Fix "no observation by default" configuration logic
bd207ff42a