chore: enforce pnpm@v9

[danielleroux]

🆕 What is the new behavior?

Replace packageManager property with engine.pnpm property

🏁 Checklist

A pull request can only be merged if all of these conditions are met (where applicable):

• [ ] 🦮 Accessibility (a11y) features were implemented
• [ ] 🗺️ Internationalization (i18n) - no hard coded strings
• [ ] 📲 Responsiveness - components handle viewport changes and content overflow gracefully
• [ ] 📄 Documentation was reviewed/updated (pnpm run docs)
• [ ] 🧪 Unit tests were added/updated and pass (pnpm test)
• [ ] 📸 Visual regression tests were added/updated and pass (Guide)
• [ ] 🧐 Static code analysis passes (pnpm lint)
• [x] 🏗️ Successful compilation (pnpm build, changes pushed)

👨‍💻 Help & support

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 9c79f302bc0713ff4466973cc3d7dfca1110302a

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