PR #32272 added a separate models_mgmt suite for the /model/new, /model/update,
and /model/delete lifecycle; the management suite that merged later covers the
sibling key/team/user/organization routes, and two suites for one route family
is one too many. Fold the four model tests in as a second test file, merge the
model methods into ManagementClient (find_deployment, update_model_tpm, a
strict delete_model_strict matching the delete_key_strict naming, and the raw
create_model_status), and port the typed pieces to models.py: DeploymentParams
mirroring LiteLLM_Params so /model/info assertions can reach any configured
knob, tpm on LiteLLMParamsBody, and ModelUpdateParams/ModelUpdateBody.
All 12 suite tests verified live against the split stage deployment
cfe2df0db6