apigateway: private domain name L2 construct

[jtmthf]

Description

As initially proposed here aws/aws-cdk/issues/33352, the goal is to create a set of L2 constructs for API Gateway custom domain names for private APIS. The three proposed constructs would be as follows:

• PrivateDomainName maps to CfnDomainNameV2
• PrivateBasePathMapping maps to CfnBasePathMappingV2
• DomainNameAccessAssociation maps to CfnDomainNameAccessAssociation

The resulting solution would provide a straightforward path for users to launch private apis with custom domain names that matches the developer experience already available for public custom domain names.

Roles

Role	User
Proposed by	@jtmthf
Author(s)	@jtmthf
API Bar Raiser
Stakeholders

See RFC Process for details

Workflow

• Tracking issue created (label: status/proposed)
• API bar raiser assigned (ping us at #aws-cdk-rfcs if needed)
• Kick off meeting
• RFC pull request submitted (label: status/review)
• Community reach out (via Slack and/or Twitter)
• API signed-off (label status/api-approved applied to pull request)
• Final comments period (label: status/final-comments-period)
• Approved and merged (label: status/approved)
• Execution plan submitted (label: status/planning)
• Plan approved and merged (label: status/implementing)
• Implementation complete (label: status/done)

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