expose ingest endpoint as part of ec_observability_project resource

[vigneshshanmugam]

Overview

Would like to see the endpoint of Ingest which is available when creating a serverless observability project. Currently we have to replace the manually get one of the existing application endpoints ( example - apm endpoint replace it withingest url).

Possible Implementation

The project-api schema already exposes these endpoints when creating new observability projects, it should be possible to just add that to the list of exposed endpoints in terraform module.

Context

We are heavily relying on the ec terraform provider for most of our local setup which we are using in multiple projects for CSP based Ingestion needs, Serverless forwarders for AWS/Azure etc. This would be a nice to have as we can use the exposed ingest endpoint without having to manually replace the url.

Local setup for Azure - https://github.com/elastic/elastic-serverless-forwarder-otel-poc/pull/54