Add push endpoint for jfr/pprof pyroscope/phlare protocol

[tomershafir]

Request

Add push endpoint for jfr/pprof pyroscope/phlare protocol

Use case

Profiles are generally events and less fit the pull model like metrics (there are tradeoffs, of course). Thus, I think grafana agent should support the common case of user applying a push model with a jfr/pprof pyroscope/phlare endpoint, providing intermediate collector functions external to the data plane, with batching being a critical feature, and also filtering. I may be able to help contribute.

[rfratto]

cc @grafana/grafana-agent-profiling-maintainers WDYT?

[cyriltovena]

We are actually planning to do node wise profiling with async-profiler so no need to pull jfr.

[ptodev]

Hi @tomershafir! Thank you for raising an issue. I'm going to close this one, because it seems to be a duplicate of #270.