Kibana 8.12.0 introduced a new bundled X-Pack plugin (x-pack/plugin/apm: introduce x-pack-apm plugin · axw/elasticsearch@2aebfcc · GitHub) that allows installing APM related index templates etc. without the need for configuring Fleet.
I've been unable to find in the Kibana docs the correct way in Kibana's configuration to enable the plugin
cc @axw -- Not sure if you're active on here but I recall you saying how to do it on Slack a while ago (before the standalone plugin was implemented), sadly the history has since gone