feat(nuxt3): extends support for server/ directory

[kevinmarrec]

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 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)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Following up nuxt/nuxt#13367 (extends support progress) this PR allows extending server/ directory for extended config layers

TO DO

• Extends support for server directory
• Improve code to have less redundant logic ?
• Extends support for serverMiddleware config key in layers => maybe later ? /cc @pi0

[netlify]

✔️ Deploy Preview for nuxt3-docs canceled.

🔨 Explore the source changes: cbf6b68

🔍 Inspect the deploy log: https://app.netlify.com/sites/nuxt3-docs/deploys/6230b8f0fd08910009bce6a3

[pi0]

This is an experimental feature and probably chaning little bit behavior when switcing to nitropack.

[yassilah]

Hi! I love the new extends feature of Nuxt 3 and I'm really amazed by the possibilities it offers. However, when it comes to extending the server directory, I would also expect it to be possible for an "upper" layer to override a "lower" layer with default handlers. Right now, because of the order of the scanDirs, it isn't possible; though I found a quick workaround by enforcing it manually. Maybe this should be the default behavior?

useNuxt().hook('nitro:init', nitro => {
    nitro.hooks.hook('rollup:before', nitro => {
        nitro.options.scanDirs.reverse()
    })
})