Provide better way to monitor JMX metrics for Bitbucket 8.x while using Mesh Sidecar

As of Bitbucket 8.0, Git operations are now run in the mesh sidecar by default. This sidecar JVM is launched directly from the Bitbucket JVM, and therefore does not have startup scripts. This means users have to configure the sidecar JVM options through the Bitbucket server(bitbucket.properties) for items such as JMX settings, heap dump, or gc logging configuration.

To enable JMX monitoring for Bitbucket 8.x, JMX must be enabled on both the Bitbucket main process and the Mesh sidecar process.
However, adding JMX-related parameters for the Mesh Sidecar can only be done via the "bitbucket.properties" file. This can be a bit complicated if you have a multi-node setup, as the "bitbucket.properties" file is shared and only allows you to define one IP address.

To overcome this challenge, each Bitbucket Node must have a local "bitbucket.properties" file with the corresponding local Node IP and then be symbolically linked to the BITBUCKET_HOME/shared/ directory.

Here are the steps to enable JMX monitoring on the Bitbucket Mesh Sidecar:

• Enable JMX on the "BITBUCKET_HOME/mesh/mesh.properties" files on all the Nodes by adding the following line:

  jmx.enabled=true
  

• Modify the "bitbucket.properties" file as follows to add JVM arguments to the Mesh Sidecar Java process:

  plugin.bitbucket-git.mesh.sidecar.jvmArgs[0]=-Dcom.sun.management.jmxremote.port=4444
  plugin.bitbucket-git.mesh.sidecar.jvmArgs[1]=-Djava.rmi.server.hostname=<node_ip_address>
  plugin.bitbucket-git.mesh.sidecar.jvmArgs[2]=-Dcom.sun.management.jmxremote.ssl=false
  plugin.bitbucket-git.mesh.sidecar.jvmArgs[3]=-Dcom.sun.management.jmxremote.password.file=/var/atlassian/bitbucket_jmx.access
  

For more information on adding JVM arguments to the Mesh sidecar process, please refer to the article "How to pass JVM arguments to the Mesh sidecar" (https://confluence.atlassian.com/bitbucketserverkb/how-to-pass-jvm-arguments-to-the-mesh-sidecar-1142425281.html).

After restarting, you should now see JMX enabled on the Bitbucket Mesh sidecar process.

Request is to make JMX monitoring on Bitbucket 8.x with the Mesh sidecar much cleaner or easier without having to maintain a separate "bitbucket.properties" file for each node.