Provide a init function for frontend observability [Hilla]

[heruan]

The Hilla demo uses this function to initialize the frontend observability insturmentation:

observability-kit/observability-kit-demo-hilla/frontend/utils/telemetry.ts

Lines 8 to 27 in e5d1200

	export default function initTelemetry(): void {
	const provider = new WebTracerProvider();
	provider.register({
	contextManager: new ZoneContextManager(),
	});
	provider.addSpanProcessor(
	new SimpleSpanProcessor(
	new HillaEndpointExporter({
	// eslint-disable-next-line @typescript-eslint/no-misused-promises
	endpoint: ObservabilityEndpoint.export,
	}),
	),
	);
	registerInstrumentations({
	instrumentations: [new DocumentLoadInstrumentation()],
	});
	}

We should provide this functionality embedded in the kit to facilitate the initialization of frontend observability.