fix(router): enable health checks during startup

[Noroth]

Motivation and Context

Health checks are currently only available after the router has been initialized. The expected intended behavior is, that the health checks are available during setup and report liveness and correct readiness information.

ready

• during initialization -> false
• after initialization -> true

Checklist

• I have discussed my proposed changes in an issue and have received approval to proceed.
• I have followed the coding standards of the project.
• Tests or benchmarks have been added or updated.
• Documentation has been updated on https://github.com/wundergraph/cosmo-docs.
• I have read the Contributors Guide.

[github-actions]

Router image scan passed

✅ No security vulnerabilities found in image:

ghcr.io/wundergraph/cosmo/router:sha-6177fd7277122d1e94d310aeb3564f9b58e59f1c

[jensneuse]

Can you add a test where you mock the cache warmup loader interface?

1. start server
2. check live true ready false
3. set mock to "finish" warmup phase
4. check live true ready true

[Noroth]

Can you add a test where you mock the cache warmup loader interface?

1. start server
2. check live true ready false
3. set mock to "finish" warmup phase
4. check live true ready true

This is a good question. The StartRouter is a blocking operation, also in Testenv we start the router blocking... So basically all logic that we implement in the callback function will be called once the router has finished setting up.
Also we need the xEnv to know the endpoint to call the router so we can't do it in parallel within the test function.

Currently I tested it manually with a delay timer and running curl requests.

I think we can do that, but it might take a bit of time to have a safe implementation in the testenv.

[StarpTech]

LGTM