v0.22.1 — Native HTTP response contracts

The native HTTP API now declares typed health, readiness, active-profile and job responses in OpenAPI.
It describes 202 acceptance, queue rejection with Retry-After, volatile history, errors and binary/range
latent downloads. Response fields and executor extensions are preserved; no inference algorithm, model,
attention default or numeric result changes. HTTP tests use a controlled executor without GPU inference.
See the HTTP contract. Published 0.18.0 containers keep their original schema; install the
0.22.1 server package to use the updated declarations.