Integrate monitoring category with CloudWatch RUM

### Is this feature request related to a new or existing Amplify category?

New category

### Is this related to another service?

CloudWatch

### Describe the feature you'd like to request

As a developer, I want to track Core Web Vitals of my Amplify application via CloudWatch RUM so that I can give customers the best experience.

Refs: https://aws.amazon.com/blogs/aws/cloudwatch-rum/

### Describe the solution you'd like

Integration as a category would be the great experience. This proposal needs a collaboration with library team.

1. Run `amplify add monitoring` to start configuration
2. Choose what `App monitor name` should take a pace in CloudWatch RUM?
3. import { CloudWatchRUM } from 'aws-amplify'; and initialize in app
4. Then you will be able to see Core Web Vitals in dashboard on CloudWatch RUM
+ Stretch goal would be to integrate this feature on Console

### Describe alternatives you've considered

I've implemented via Kinesis and QuickSight which took more than 6 steps and was hard to maintain.
https://watilde.medium.com/improve-ux-by-observability-in-front-end-with-amplify-and-quicksight-e7083ec1913b

### Additional context

Many users today are struggling to observe issues of front-end in production and it is not simple to integrate tracking system as there was not many best practices, particularly within AWS. It is a blocker for large scale application developers to migrate from traditional server app to SPA.

### Is this something that you'd be interested in working on?

- [ ] 👋 I may be able to implement this feature request
- [ ] ⚠️ This feature might incur a breaking change