feat(nuxt): definePageMeta in "pages:extend"

[huang-julien]

🔗 Linked issue

#19955

❓ 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

Hi 👋 , this PR add the result of the page:extend hook so pages added within modules can be also transformed.

📝 Checklist

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

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[danielroe]

You are fast!! 🔥

The main issue I see here is that the page routes may change after the initial modules are loaded, for example if the user adds new files to the pages directory or there is some custom logic within a user pages:extend hook that changes.

[huang-julien]

I see... then should we just transform both dirs and pages ?
at module:before ?

[danielroe]

While reviewing, it occurred to me we could take the opportunity to rework how the page meta plugin works, which should improve performance more generally by having less parsing of the code. I've opened a PR at #20628. Would love your thoughts... 🙏

[huang-julien]

closing in favor of #20628