chore: migrate to pnpm and upgrade to node 24

[cblanc]

Summary

• Migrate CI workflow from npm to pnpm with automated caching
• Upgrade CI and release workflows to Node.js 24
• Bump pnpm to latest version (10.33.0)
• Update mock script to use pnpm

Test plan

• CI workflow passes with pnpm
• Release workflow passes with node 24
• Mock script works correctly

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Project	Deployment	Actions	Updated (UTC)
openapi	Building	Preview, Comment	Mar 26, 2026 10:27am

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Status	Name	Latest Commit	Updated (UTC)
❌ Deployment failed View logs	openapi	29386c6	Mar 26 2026, 10:28 AM

[idealbot]

🎉 This PR is included in version 4.16.1 🎉

The release is available on:

• GitHub release
• npm package (@latest dist-tag)

Your semantic-release bot 📦🚀