[Feature Request] Amplify codegen - auto create sample input / inputs details

### Before opening, please confirm:

- [X] I have installed the latest version of the Amplify CLI (see above), and confirmed that the issue still persists.
- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-codegen/issues?q=is%3Aissue+).
- [X] I have read the guide for [submitting bug reports](https://github.com/aws-amplify/amplify-codegen/blob/master/CONTRIBUTING.md#bugs).
- [X] I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

### How did you install the Amplify CLI?

npm

### If applicable, what version of Node.js are you using?

v16.13.0

### Amplify CLI Version

2.27.1

### What operating system are you using?

Windows

### Amplify Codegen Command

codegen

### Describe the bug

Similar to how `amplify codegen` creates the respective classes with query / mutation / subscriptions, can there be a documentation or sample inputs created with all the queries and minimal inputs i.e. only mandatory inputs so that the front-end dev or user would have a sample which they can check with? This helps in maintaining documentation / sample inputs for the AppSync APIs.

### Expected behavior

This is a new feature request.

### Reproduction steps

This is a new feature request.

### GraphQL schema(s)

```graphql
# Put schemas below this line

```

### Log output

```
# Put your logs below this line

```

### Additional information

_No response_