Port Auditbeat and Packetbeat to the agent V2 control protocol

[cmacknz]

This will be done as a follow up to #32673 which has already gotten quite large. The changes will be merged to the same Beats V2 feature branch while we wait for the V2 protocol to be fully supported in agent.

The changes should in theory mirror the changes that were already made for Filebeat and Metricbeat.

• The Packetbeat agent spec file looks like it only includes the input selectors to tell agent when to start Packetbeat. I expect it will not require any changes besides use of the new V2 protocol client.
• The Auditbeat agent spec file is as complex as the one for Metricbeat, as Auditbeat is internally based on Metricbeat. This will require some closer investigation and possibly some help from @andrewkroh and team.

[elasticmachine]

Pinging @elastic/security-external-integrations (Team:Security-External Integrations)

[elasticmachine]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)