signalfx/splunk-otel-collector ? reverse-engineered prompt

Build me a Splunk OpenTelemetry Collector style service in Go that gives people one place to receive, process, and forward metrics, traces, and logs. It should work in both agent mode for a single machine and gateway mode for shared collection, then send data to Splunk Observability Cloud for APM and infrastructure monitoring. It should also be able to forward to Splunk Cloud or Splunk Enterprise through HEC when needed.

I want it to feel production ready, with sensible default configs, clear examples, health and troubleshooting guidance, and support for common environments like Kubernetes, Linux, Windows, and Docker. Include starter configs for general use and a good starting point for Linux log collection. Packaging and deployment files should be there so someone can actually install and run it, not just compile it.

Please follow the normal OpenTelemetry Collector model, but make the setup friendly for Splunk users with access token, realm, ports, and sizing in mind. Check the current Splunk and OpenTelemetry docs online if you need to fill in details.