Enable using JMX Metrics instrumation as a library, not only through javaagent

[adamw]

Is your feature request related to a problem? Please describe.

I'd like to use the Otel <-> JMX integration as a library, without the need to install a Java Agent, as described currently on: https://github.com/open-telemetry/opentelemetry-java-instrumentation/blob/main/instrumentation/jmx-metrics/javaagent/README.md

I don't think the javaagent code is published, I've been only able to find the library on Maven Central:

<dependency>
    <groupId>io.opentelemetry.instrumentation</groupId>
    <artifactId>opentelemetry-jmx-metrics</artifactId>
    <version>2.8.0-alpha</version>
    <scope>runtime</scope>
</dependency>

Describe the solution you'd like

My goal is to include all observability-related setup as code, in the main method of the application. I've got OTEL working without problems using AutoConfiguredOpenTelemetrySdk.initialize().getOpenTelemetrySdk(), but to get the JMX integration I think I'll have to copy the initialisation code from JmxMetricInsightInstaller.java for now.

Ideally. I'd be able to do sth like JmxMetrics.initialise(openTelemetry), given an instance of OpenTelemetry.

Describe alternatives you've considered

No response

Additional context

No response