Versioning and deprecation policy
`/v1` is a stable contract; incompatible changes require a new major version.
Stable v1 contract
Adding fields, endpoints, or optional parameters is compatible.
Removing fields, changing types, adding required inputs, or changing semantics is incompatible and requires
/v2.Deprecation
An endpoint scheduled for removal is announced in the changelog at least 90 days ahead. Responses include Deprecation: true, an RFC-date Sunset, and a Link rel="deprecation" header to the migration guide.
Documentation version
The documentation can be published in several versions. The version selector is not shown while v1 is the only published version; it appears in the same place when v2 is released.