[SDK Sentinel] Allow delayed activity visibility in pause test

[sdk-sentinel-bot]

Caution

This PR contains untrusted AI-generated code. Do not approve or run CI until a maintainer has reviewed the diff. SDK Sentinel verified that GitHub Actions remained approval-gated with zero executable jobs when this PR was opened.

Summary

• CI evidence: failed CI job · workflow run · first known failure

Prevent a load-sensitive false failure in the activity pause/unpause test. The [first captured failing main run](https://github.com/temporalio/sdk-python/actions/runs/36917506838) missed the activity, while a [subsequent successful main run](https://github.com/temporalio/sdk-python/actions/runs/36925546375) passed after an unrelated change.

Root cause

The test allowed five seconds for its initial activity to appear in server state. Source logs show that deadline expiring just as the activity started and worker shutdown began, so the assertion observed a transient absence.

Fix

Use a ten-second eventual-observation budget at this test's initial pending-activity handshake. This preserves the state assertion and does not retry the test.

Validation

Three unchanged and three changed focused Linux runs passed. The unchanged baseline and fixed repository validator passed. macOS Python 3.10 CI remains required because the natural delay was not reproduced locally.

Validation status: ci-validation-required

• Flake confidence: high
• Fix confidence: medium
• Value: medium
• Patch scope: standard — 1 changed file; 676 B
• Local reproduction: not-reproduced — Three unchanged focused Linux attempts passed; macOS Python 3.10 was unavailable locally.
• Regression coverage: pass-after-only — The existing focused test passed three times after the isolated timing-budget change; no new test was added for this test-only correction.
• Unchanged baseline (Poe lint, bridge lint, and editable build) — passed
• Independent candidate (Poe lint, bridge lint, and editable build) — passed

Investigator-run checks

• for attempt in 1 2 3; do poe test -s -k test_activity_pause_unpause \|\| exit; done — passed; 3 attempt(s). All three post-change Linux Python 3.14 attempts passed; three unchanged attempts also passed.
• .ci-flake-runtime/input/validate.sh — passed; 1 attempt(s). Canonical formatting, typing, documentation, Rust lint, and editable-build validation passed; the trusted unchanged baseline also passed.

Required target CI

• Continuous Integration / build-lint-test (3.10, macos-arm)

Residual risks

• Linux did not reproduce the captured scheduling delay.
• The ten-second budget provides measured headroom but cannot bound every possible runner stall.

Automation provenance

• Investigator workflow
• Base SHA: 03cdb189e7c05c7f37ff7818f589d1dfbc1b4b6a

If this finding should not be fixed, apply the sdk-sentinel:false-positive label and close the PR. Sentinel will suppress the finding until its affected source changes.

SDK Sentinel recurrence history

• Unique failed CI run attempts: 1
• First occurrence: 2026-10-01 20:10 UTC
• Latest occurrence: 2026-10-01 20:10 UTC
• Recent occurrences:
  • 2026-10-01 20:10 UTC — failed CI job