[EBT] Schema-based event&context validation (only in dev mode)

[afharo]

When using the EBT APIs, developers need to call analytics.registerEventType({ eventType, schema }) and analytics.reportEvent(eventType, { ...eventProperties }).

This can cause a disconnection between the schema and the eventProperties that can lead to reporting unexpected data.

Let's add a schema-based validation step to throw when reporting an event that doesn't adhere to the schema specification (only when running in dev mode):

kibana/packages/analytics/client/src/analytics_client/analytics_client.ts

Lines 106 to 108 in 7226982

	if (this.initContext.isDev) {
	// TODO: In the future we may need to validate the eventData based on the eventType's registered schema (only if isDev)
	}

We may use the schema_to_io-ts implementation from the POC: https://github.com/elastic/kibana/pull/95960/files#diff-5eda84ca820acad68804d4415017a209cc784672b6512871063b1f9134abc7e4

NOTE: While the analytics.registerContextProvider API is less prone to this error, we may want to add the same validation there:

kibana/packages/analytics/client/src/analytics_client/context_service.ts

Lines 35 to 37 in 7226982

	if (this.isDevMode) {
	// TODO: In the future we may need to validate the input of the context based on the schema (only if isDev)
	}

[elasticmachine]

Pinging @elastic/kibana-core (Team:Core)

[afharo]

Dynamically import io-ts validation library so it's not actually loaded in production!