fix(vector stores): refresh server poll intervals

[Hughhhhcoder]

• I understand that this repository is auto-generated and my pull request may not be merged

Changes being requested

When poll_interval_ms is omitted, the vector-store polling helpers currently assign the first response's openai-poll-after-ms value back to poll_interval_ms. That makes the value appear caller-specified on later iterations, so subsequent server hints are ignored.

For example, two pending responses with 100 ms and 2000 ms hints currently sleep for [0.1, 0.1] seconds instead of [0.1, 2.0].

This change keeps an explicitly supplied interval fixed, while resolving an omitted interval from every pending response. The behavior now matches the response-scoped hint handling in the other OpenAI SDK polling implementations.

The regression covers all four public vector-store polling paths:

• Files
• AsyncFiles
• FileBatches
• AsyncFileBatches

Additional context & links

The patch is limited to the SDK-owned src/openai/lib/_vector_stores.py helper and its focused tests. It does not change any public signature, request header, terminal-state behavior, or generated resource file.

Validation:

• Before the fix, the new regression failed all 4 variants with [0.1, 0.1].
• Focused Vector Store matrix:
  • Pydantic v2: 252 passed
  • Pydantic v1: 252 passed
• Full non-functional test matrix:
  • Pydantic v2: 11,236 passed, 144 skipped
  • Pydantic v1: 11,222 passed, 158 skipped
• ./scripts/lint: Ruff, Pyright, mypy, and import check passed
• Castiron custom-code budget: passed, 6566 / 10000 lines; no new custom-code files or generated customizations
• git diff --check: passed

[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 2026-09-01T10:21:06.739423Z	772a642	PR opened
🔒 Security Review	✅ Completed 2026-09-01T10:22:08.482793Z	772a642	PR opened

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[sylvesterkaczmarek]

I traced this through all four vector-store polling paths. The important part is that an omitted poll_interval_ms now remains omitted across iterations, so _get_poll_interval_ms(response.headers) is evaluated against each pending response instead of the first server hint becoming accidental caller state.

An explicit interval is still stable: it continues to set X-Stainless-Custom-Poll-Interval once and is selected on every iteration. When no server hint is present, _get_poll_interval_ms also preserves the existing 1000 ms fallback.

The two-response 100 ms -> 2000 ms regression directly pins the failure mode, and the shared parameterized test covers the sync/async file and file-batch entry points. I don't see a blocking behavior change beyond the intended response-scoped hint refresh.