Port the token introspection helpers and link-share token renewal to
/api/v2:
- GET/POST /token/test both return a plain 200 "ok"; v1's POST 418
teapot easter egg becomes an ordinary success.
- GET /routes lists the scoped-token routes for both API versions
(models.GetAPITokenRoutes already merges v1 + v2).
- POST /user/token renews a link-share JWT; user tokens are rejected
(they must use the refresh-token flow), mirroring v1.
The renew response inlines the token field rather than returning
auth.Token directly, since Huma names schemas by bare type and a
top-level auth.Token body would collide with user.Token.
38d7fa3c88