Move telemetry initialization logic to service/telemetry

[mx-psi]

Telemetry initialization is currently split between the service/telemetry package and the service package in the telemetry.go package. This causes some issues:

1. The telemetry.TracerProvider method returns a tracer provider that is never used in practice. It is used here

   opentelemetry-collector/service/service.go

   Line 103 in 3089ea8

   TracerProvider: srv.telemetry.TracerProvider(),

   and then immediately overridden by the telemetry initializer one.

   opentelemetry-collector/service/service.go

   Line 115 in 3089ea8

   srv.telemetrySettings.TracerProvider = srv.telemetryInitializer.tp

   The telemetry initializer tracer provider is built from scratch

   opentelemetry-collector/service/telemetry.go

   Lines 101 to 111 in 3089ea8

   	func (tel *telemetryInitializer) initTraces(res *resource.Resource, cfg telemetry.Config) (trace.TracerProvider, error) {
   	opts := []sdktrace.TracerProviderOption{}
   	for _, processor := range cfg.Traces.Processors {
   	sp, err := proctelemetry.InitSpanProcessor(context.Background(), processor)
   	if err != nil {
   	return nil, err
   	}
   	opts = append(opts, sdktrace.WithSpanProcessor(sp))
   	}
   	return proctelemetry.InitTracerProvider(res, opts)
   	}

   without using telemetry.TracerProvider. I believe because of this the sampling configuration set on service/telemetry is ignored.

   opentelemetry-collector/service/telemetry/telemetry.go

   Lines 47 to 50 in 3089ea8

   	tp := sdktrace.NewTracerProvider(
   	// needed for supporting the zpages extension
   	sdktrace.WithSampler(alwaysRecord()),
   	)

2. Parts of telemetry are initialized in service/telemetry, while others are initialized in service. In particular, the logger is initialized in service/telemetry, the tracer provider can be initialized in both but only the service one is used, and the metrics provider is only initialized in service.

I think we should consolidate telemetry initialization to the service/telemetry package and have methods to generate the telemetry providers from config as part of the public API. This would mean adding a new method to telemetry.Telemetry to handle registration of process metrics, currently done in the service via the telemetry initializer

opentelemetry-collector/service/service.go

Lines 210 to 211 in 3089ea8

	// The process telemetry initialization requires the ballast size, which is available after the extensions are initialized.
	if err = proctelemetry.RegisterProcessMetrics(srv.telemetryInitializer.ocRegistry, srv.telemetryInitializer.mp, obsreportconfig.UseOtelForInternalMetricsfeatureGate.IsEnabled(), getBallastSize(srv.host)); err != nil {

One challenge here is that proctelemetry depends on service/telemetry for the generated configuration; if we don't want to expose the OpenCensus registry we need to refactor the current package structure (e.g. by having a new service/telemetry/config package).

cc @codeboten since this may overlap with the work on #7532

[mx-psi]

Removed this from Collector v1 project board based on #10643