Remove expired npm audit exception

[Widthdom]

Summary

• Fix the javascript-tests failure in run 33883052995, which was caused by the expired GHSA-mh99-v99m-4gvg audit exception.
• Remove the expired exception now that the locked Jest dependency graph selects patched brace-expansion releases through the existing npm overrides.
• Require the npm audit exception list to remain empty and update the English/Japanese testing guide and changelog.

Validation

• npm ci — completed; 0 vulnerabilities
• npm run test:js — 190 passed
• npm run audit:high — passed with 0 findings and 0 active exceptions
• Focused Release test — 1 passed
• Full Release tests — 2,165 passed, 1 skipped, 0 failed
• dotnet format FolderDiffIL4DotNet.sln --verify-no-changes --no-restore — passed
• git diff --check origin/main..HEAD — passed

OSS review fix mapping

• The six-item OSS review fix mapping is not applicable; this PR is narrowly scoped to the reported pipeline failure.

Checklist

• I read AGENT_GUIDE.md.
• I used the nildiff command name in user-facing text.
• I ran the relevant tests.
• I ran the Release configuration test when feasible.
• I updated docs, samples, and CHANGELOG.md when behavior changed.
• I did not add secrets, tags, or publish steps.
• I used explicit git add <file> paths only.

日本語

• AGENT_GUIDE.md を読んだ。
• ユーザー向けの文面では nildiff を使った。
• 関連テストを実行した。
• Release 構成のテストを実行した。
• ドキュメントと CHANGELOG.md を英日同期で更新した。
• シークレット、タグ、公開手順を追加していない。
• git add <file> で明示的に追加した。