databases/py-dbt-semantic-interfaces: new port

dbt-semantic-interfaces contains the shared semantic classes, default
validation, and tests designed to be used by both the dbt-core and MetricFlow
projects. By centralizing these shared resources, we aim to maintain consistency
and reduce code duplication across both projects.

Features:

• Protocols for shared semantic classes: Define the interfaces and common attributes that must be implemented by the objects in both projects.
• Validation: Ensure that the objects comply with the expected structure and constraints.
• Tests: Ensure that the objects' behavior is consistent and correct across both projects.

PR: 274581
Author: Pat Maddox <pat@patmaddox.com>