aws_opensearchserverless: L2 constructs

### Describe the feature

L2 construct for aws_opensearchserverless domains which ideally implements the same interfaces as aws_opensearchservice.

### Use Case

Creating cdk constructs for opensearch serverless has similar user experience to writing cloudformation templates. This makes also dependent task such as adding the opensearch serverless as appsync datasource very cumbersome.

### Proposed Solution

Create L2 "Domain" for opensearch serverless which implements IDomain interface.

### Other Information

_No response_

### Acknowledgements

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

### CDK version used

2.122.0

### Environment details (OS name and version, etc.)

Windows

No files, tests, or entry points are identified in the issue. Start by reviewing the existing aws_opensearchservice L2 constructs and the IDomain interface, then determine the behavior needed for an aws_opensearchserverless Domain that supports the stated AppSync data-source use case.

Written by the indexing model from the issue text.