feat(FN-3593): add test isolation CI enforcement, fix stuck-requeue race, a

This merge lands five FN-3593 commits establishing a test isolation contract with a new `scripts/check-test-isolation.mjs` guard that scans for accidental `beforeEach`/`afterEach`/`beforeAll`/`afterAll` in setup helpers, plus per-package `setup-test-isolation.ts` bootstraps that canonicalize the pat

Fusion-Task-Id: FN-3593

packages/cli/vitest.config.ts

@@ -47,7 +47,6 @@ export default defineConfig({
     // run with file parallelism enabled.
     exclude: ["**/node_modules/**", "**/dist/**", "src/__tests__/build-exe*.test.ts"],
     setupFiles: [
-      "./src/__tests__/setup-test-isolation.ts",
       resolve(__dirname, "../core/src/__test-utils__/vitest-setup.ts"),
     ],
     globalSetup: [resolve(__dirname, "../core/src/__test-utils__/vitest-teardown.ts")],