Two test-infrastructure fixes from agent #1's flake-stabilization pass.
Skipped its DESC-order assertion rewrite (semantically equivalent no-op
that conflicted with the prior boilerplate consolidation in 848a226ca)
and its vitest.config additions (already in flight on main).
1. vitest-setup.ts: completedSubprocessFailures was a plain string[]. When
a 30s subprocess-guard timer fired during a *later* test's execution
window (because the owning test ran for e.g. 40s under its 60s
timeout budget), the failure surfaced in the innocent successor test's
afterEach. Typed the array as { ownerTestName, message }[] and filter
on the current test name; orphaned entries are dropped silently.
2. worktree-contamination-attribution.real-git.test.ts: afterEach rm
occasionally hits ENOTEMPTY on macOS when a git rebase internal dir
isn't fully flushed. Added maxRetries: 3, retryDelay: 100.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
