fix(e2e): audio/images propagation predicates tolerate transport failures

[jarvis9443]

CI flake root-cause (seen on #587's e2e job): audio-images-usage-e2e polls waitConfigPropagation with a bare fetch — when the DP drops the connection mid-multipart-write while the route is still propagating, the predicate throws TypeError: fetch failed (EPIPE) instead of returning false, failing the spec. Both call sites now wrap the probe in try/catch → false, the same contract every other spec's predicate follows. Test-only change.

Summary by CodeRabbit

• Tests
  • Enhanced audio and image generation endpoint tests to more robustly handle connection failures during propagation verification, improving test reliability without affecting user-facing functionality.

Part of api7/AISIX-Cloud#519 (surfaced while landing finding B.8's PR).

Closes api7/AISIX-Cloud#519

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Run ID: 71ad7ae8-290c-4f47-b7e8-7f662679c901

📥 Commits

Reviewing files that changed from the base of the PR and between 20cd4a4 and d558b10.

📒 Files selected for processing (1)

• tests/e2e/src/cases/audio-images-usage-e2e.test.ts

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📝 Walkthrough

Walkthrough

Updates E2E test propagation readiness checks for both /v1/images/generations and /v1/audio/transcriptions endpoints. The tests now wrap fetch requests in try/catch blocks during waitConfigPropagation to treat transport errors as "not ready yet" instead of propagation failure, then assert HTTP 200 and poll metrics for usage events after propagation completes.

Changes

Propagation readiness with transport error tolerance

Layer / File(s)	Summary
Error-tolerant propagation gating for image and audio tests tests/e2e/src/cases/audio-images-usage-e2e.test.ts	Images and audio usage-event readiness checks wrap fetch requests in try/catch to treat transport failures as transient "not ready" signals during propagation polling, advancing only when the request succeeds with .ok.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: updating the audio/images propagation predicates in E2E tests to handle transport failures gracefully.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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