docs: add example plugin for handing redirects

[mattmess1221]

🔗 Linked issue

#142

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSDoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

• Adds an example showcasing a plugin for rewriting redirects.
• To simplify running of nuxt prepare, I also added zx as a dev dependency and wrote scripts/prepare-all.ts to prepare every directory containing a nuxt.config.ts file. Not sure how I feel about that change compared to adding examples as a pnpm package and using pnpm --filter './examples/*' exec nuxt prepare or just hard-scripting the prepare of each example.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[johannschopplich]

@mattmess1221 Thanks for the PR. Love that setup. 🙂

PS.: I love the addition of zx!