test(core): fix error message assertions and unskip withExponentialBackoff tests

[mian-abd]

Description

core/util/withExponentialBackoff.ts is the retry helper wrapping every LLM call in core/llm/index.ts (chat fetch + embeddings). Its test file was skipped wholesale via describe.skip because two assertions used an incorrect expected error string: "Failed to make API call after max tries" is not a substring of the actual implementation message "Failed to make API call after ${maxTries} retries".

This PR:

1. Fixes the two assertion strings to match the actual error message (uses the stable prefix "Failed to make API call after").
2. Removes describe.skip so all 6 existing tests run.
3. Adds 3 new tests covering the previously-untested retry triggers in the implementation: "overloaded" substring, "malformed json" substring, and "code": 429 JSON-body regex.

No implementation code is changed.

Checklist

• I've read the contributing guide
• The relevant docs, if any, have been updated or created — N/A (test-only)
• The relevant tests, if any, have been updated or created

Screen recording or screenshot

N/A — test-only change with no user-visible behavior.

Tests

All changes are in core/util/withExponentialBackoff.test.ts. Verified locally via cd core && npm test -- withExponentialBackoff — 9 tests pass (6 previously-skipped + 3 new). ESLint and Prettier clean.

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Summary by cubic

Fixes and re-enables the withExponentialBackoff test suite, and adds coverage for key retry conditions. Test-only; no runtime changes.

• Bug Fixes

  • Matched expected error string to the stable prefix “Failed to make API call after”.
  • Unskipped the suite so all existing tests run.

• New Features

  • Added tests for retry triggers: “overloaded”, “malformed json”, and JSON body with "code": 429.

^{Written for commit 8bc8d02. Summary will update on new commits.}

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[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}