Move main.go config into controller package

[dmathieu]

This is the first PR moving the logic in main.go into a controller package, so that logic can be shared with the collector receiver setup.
See #160 (comment)

This first PR moves the arguments configuration and validation into the new package.

[florianl]

What about naming this internal package args instead of controller?
From a controller I expect something different, than providing a general configuration and validate it.
As this package is likely reused in the OTel profiling controller part, it should not get mixed and suggest something it doesn't do.

Suggested change

	package controller // import "go.opentelemetry.io/ebpf-profiler/internal/controller"
	package args // import "go.opentelemetry.io/ebpf-profiler/internal/args"

[dmathieu]

This is meant to be the first of a few PRs, with the intent to extract the setup of main.go into a shared package.
I named this package controller, because what it will do in the end is run the agent, either standalone, or as a collector receiver.

I'm open to a name different than controller, but args would be specific to this config, which doesn't do enough to be in its own package IMHO.

[dmathieu]

CI failure is a network error.

[christos68k]

LGTM

We can further refine things (e.g. maybe move CLI setup to internal/controller/args.go) once we have a better idea of how the OTel collector integration will look.

[rockdaboot]

LGTM, thank you!