Complete API model for our system.
References:
- https://docs.google.com/document/d/1HnRcB2SaG4f4QodOaaYZT4r4GYhibqBzA8wdl2zpID0/edit?tab=t.h8qwaqvashle
- https://openapi-converter.com/json-to-yaml
- https://editor.swagger.io/
- https://smithy.io/2.0/languages/java/client/generating-clients.html
- https://smithy.io/2.0/guides/using-code-generation/generating-a-client.html