1. Proposed title of this feature request

Enable Hosted Cluster users to monitor CMO stack

2. What is the nature and description of the request?

With CMO being the stack for customers to monitor their data plane, customers also need a way to monitor that their monitoring stack works as expected.
The usual path to monitor CMO is to have an external service that receives watchdog alerts (flowing through prometheus and alertmanager) as heartbeats, and then alerting if the heartbeats stop.

This RFE requests a new feature that gives CMO users a hypershift native way to monitor their stack.

*Note: *implementation idea would be to have the hypershift stack receive the heartbeats and write metrics to the customer's cloudwatch via cloudwatch:PutMetricData. A less "hypershift native" route would be to have the customer route to an AWS lamda, and having the AWS lamda create metrics in the customer cloudwatch, which could be alerted on.

I'm looking on feedback on whether or not this is something that could serve the wider hypershift project vs being an ad-hoc self-service implementation specifically for AWS.

3. Why does the customer need this? (List the business requirements here)

Requirement to have reliable monitoring.

4. List any affected packages or components.