## Why
Switching providers or authentication could reuse a previous identity's model catalog, including its default service tier. An in-flight refresh could also overwrite a newer account's catalog after cache storage completed.
## What changed
- Require a matching provider and auth identity for disk and in-memory catalog reuse. Treat legacy entries without an identity as cache misses and fall back to bundled metadata when the in-memory identity no longer matches.
- Recheck identity after fetching and storing a catalog before publishing it.
- Renew cache freshness only when the client version, identity, and ETag match the stored entry.
- Update cache fixtures to include the configured provider and auth identity.
## Testing
Add regression coverage for provider and auth switches, credential rotation, legacy and mismatched cache entries, conditional TTL renewal, and an account switch during cache storage. Verify that API-key requests do not inherit a ChatGPT catalog's default `service_tier`, while explicit tier selection still works.
GitOrigin-RevId: e15d7ffff238d951d7a1c6a68381cbb479994146
Ahmed Ibrahim
f046cf35df