[pkg/ottl] Add support for profiles

[dmathieu]

Component(s)

pkg/ottl

Describe the issue you're reporting

We should add support for profiles in the ottlp package, so components relying on it may start adding profiles support as well.

Related: #35982

[github-actions]

Pinging code owners:

• pkg/ottl: @TylerHelmuth @kentquirk @bogdandrutu @evan-bradley

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[dmathieu]

/label help-wanted data:profiles priority:p2

[thiha-min-thant]

Hi @dmathieu , could you please assign to me? Thanks!

[dmathieu]

I can't assign issues. But I'd say feel free to start working on this.

[TylerHelmuth]

@dmathieu is there anything stateful in OTEL profiles?

[dmathieu]

Not in the OTLP, nor the collector.
The agent could have some statefulness, but nothing that's kept across restarts or gets propagated over the wire.

[TylerHelmuth]

Ok cool. In that case to make profiles compatible with OTTL all that is needed is a new ottlprofiles context in ottl/contexts.

Once that exists other components that use OTTL can be updated to use the new profiles context.