fix(ci): restore Python next validation without Rye

[jbeckwith-oai]

Python next still uses a Rye action rejected by the repository's Actions policy and an Agents consumer job already retired from main. Restore the old next baseline's CI so the separate policy bootstrap and main-to-next sync can proceed.

• Use main's approved, SHA-pinned setup-uv action. A temporary bootstrap resolves existing project/Rye dev requirements for each selected Python runtime, then installs that local lock. Require dependency wheels because old NumPy metadata omits its unsupported Python upper bound. The existing Pydantic-v1 nox lane consumes the same runtime-appropriate lock.
• Invoke lint/tests directly in that environment and match main's main-only restriction for credentialed live examples.
• Carry the approved retirement of the downstream Agents job from #3750, merged as 910b316. Its floating consumer reports type errors against SDK inputs identical to next; the SDK's own symbol and breaking-change checks remain intact. No branch rules or security gate are changed.

Committed dependency manifests/locks, SDK APIs, policy, release environments and publishing workflows remain unchanged. Preserve the supported Python matrix, HTTPX coverage and Pydantic-v1 lane. After this lands, reopen the separate policy-only PR, then sync main's full toolchain and remove the temporary bootstrap.

Validation: full hosted Python 3.10/3.14 and HTTPX2 matrix, lint, build, Python policy and breaking-change checks passed on 2de23df; the only failure was the retired Agents job. Local revised Python 3.10 bootstrap/lint pass; Python 3.14 bootstrap and focused tests pass under both Pydantic majors (201 passed, two skipped each). Final workflow-only retirement passes YAML parsing and basic diff review; fresh hosted CI and SDK-team approval remain required.

Packaging review follow-up: keep the generated runtime lock in .venv/requirements-dev.lock; Nox selects it when present and otherwise uses the committed lock. Verified the rebuilt sdist includes the committed root lock byte-for-byte and excludes the CI environment, and that both lock-selection paths work. Python 3.14 Pydantic-v1 regressions pass again (201 passed, two skipped). All hosted checks passed on e3a8ac6; fresh checks and automated reviews run after this packaging fix.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-20T05:34:39.520589Z	5a0aa29	New commits
🔒 Security Review	✅ Completed 2026-10-20T05:35:10.754148Z	5a0aa29	New commits

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