Two engine merger tests created mkdtempSync workspaces directly in tmpdir()
under the tracked `fusion-test-` prefix; under full-suite concurrent load
the post-run check-test-isolation flagged them as leaks. Route both
(`merger-no-op-fix-finalize.test.ts`, `merger-verification-fix-already-on-main.test.ts`)
through FUSION_TEST_WORKER_ROOT like sibling merger tests so they nest
inside the already-tracked worker root.
Bump engine vitest subprocess guard from 60s to 120s and testTimeout to
30s — plain git commands (branch -d, worktree remove) queued behind
system contention during `pnpm -r --workspace-concurrency=2` runs were
timing out. The guard only fires on hangs, so healthy tests pay nothing.
Also bundles in-progress dashboard mobile-breakpoint regex/CSS test
updates and docs index additions.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
