test(e2e): init-e2e-flags checks CLI existence, not freshness

[dean0x]

Problem

tests/init-e2e-flags.test.ts:105 uses existsSync(CLI_PATH) to gate the e2e test suite, which checks whether dist/cli.js exists, not whether it is fresh. A dist/cli.js built from any prior commit satisfies the gate, so running npx vitest without npm run build:cli first silently exercises stale code while tests report green.

Current Status

• Pre-existing: identified in PR feat: gate AI-attribution suppression behind typed flag with init wizard #316 (feat/315-gate-attribution-flag) review
• Suite-wide impact: gate affects all tests in the suite (5+ new cases added in PR feat: gate AI-attribution suppression behind typed flag with init wizard #316, all depending on it)
• CI safety: CI builds before testing, so CI is unaffected; risk is local development
• Confidence: 85% (from testing review)
• Related PF: cites PF-018 (build freshness contract)

Suggested Sequencing

Fixing this changes the suite-wide build-freshness contract — scoped outside PR #316's blast radius. Suggested approaches:

1. Replace existence check with freshness check (mtime(dist/cli.js) > mtime(newest src/**/*.ts))
2. Have e2e suite build into a temp dir itself (ensures freshness by construction)

Acceptance Criteria

• E2E test gate checks CLI freshness, not existence
• npx vitest without prior npm run build:cli either fails or rebuilds automatically
• Stale code is never silently exercised
• All existing e2e tests pass with new gate

Related

• PR feat: gate AI-attribution suppression behind typed flag with init wizard #316 (feat/315-gate-attribution-flag)
• Source: testing.md review finding, 2026-09-01
• Ref: tests/init-e2e-flags.test.ts:105