Support for Registry

### Description

Please add support for AgentCore Registry to create Registry and creating, approving, listing, and searching registry records for the registry in the agentcore cli. This would help agent developers and CI/CD pipelines to publish the tools, skills and agents to the registry.

### Acceptance Criteria

agentcore cli command provides option to create registry, then add, approve, list and search registry records to the registry.

### Additional Context

_No response_