Suppress dependency optimizations on `nuxt dev`

[alashchev17]

Problem

Vite's automatic dependency optimization causes disruptive "optimized dependencies changed. reloading" messages that severely impact development workflows:

1. CI/CD Testing: Playwright/Cypress tests fail with ECONNRESET errors or freeze when dependencies optimize mid-test
2. Local Package Development: Virtual links (pnpm/npm link) get overridden, breaking monorepo workflows
3. Complex Applications: Apps with many pages/routes trigger endless reloads as each page imports new dependencies during manual testing
4. Debugging Sessions: Unexpected reloads cause loss of application state

Developers need control over when optimization happens to avoid it when unnecessary.

Proposed Solution

Add a CLI flag to disable Vite's dependency optimization:

nuxt dev --suppress-dependency-optimization

This would set vite.optimizeDeps.disabled = true internally.

Use Cases

E2E Testing:

nuxt dev --suppress-dependency-optimization & npm run test:e2e

Testing Complex Apps:

# Navigate through all pages without constant reloads
nuxt dev --suppress-dependency-optimization

Monorepo Development:

# Preserve linked local packages
nuxt dev --suppress-dependency-optimization

Why This Matters

• Current workaround requires manually listing all dependencies in vite.optimizeDeps.include - impractical for large apps
• Optimization is helpful for production but often unnecessary during active development
• Developers should control when optimization occurs, not be forced into it

Implementation

Non-breaking opt-in flag that passes through to existing Vite configuration. Simple addition to the dev command args.

Would the team accept a PR for this feature?

Related: #27700, nuxt/nuxt#26783, nuxt/nuxt#27372

Additional information

• [x] Would you be willing to help implement this feature?
• [ ] Could this feature be implemented as a module?

Final checks

• [x] Read the contribution guide.
• [x] Check existing discussions and issues.