KnownVersions enum

The available API versions.

This enum lists only the currently active API versions. Retired preview versions (e.g. 2025-11-01-preview through 2026-05-01-preview) are intentionally omitted — each new preview fully supersedes the previous one, and customers are expected to adopt the latest preview. Including every shipped preview would require extensive @added/@removed decorator chains across hundreds of models, rendering the TypeSpec source unreadable and unmaintainable.

The published swagger files under preview/<retired-version>/ remain on disk for backward compatibility with existing consumers (CI pipelines, unit tests, and customer dependencies). Those swaggers are frozen and must be regenerated from a pinned commit if changes are ever needed — not from the latest main.