integrate playwright and implement persistent screenshots

[hyperrealist]

This PR integrates a playwright screenshot workflow with health_check.py and implements a mechanism to persist screenshots.

Following screenshot demonstrates the results of a test ran on raydata under user account, together with a test slack workspace.

Finally, here is an example demonstrating persistent screenshots (collected during testing):

[mrakitin]

@hyperrealist, want to follow up on the suggestions?

[hyperrealist]

@hyperrealist, want to follow up on the suggestions?

I was focused on raydata and this fell through the cracks. Will push an update soon.