[cacheComponents]: Sitemaps are flagged as 'Dynamic Routes' by default

[WarFiN123]

Link to the code that reproduces this issue

https://github.com/WarFiN123/nextjs-reproduction-app

To Reproduce

1. Enable cacheComponents in the Next.js config file.
2. Add a sitemap file.
3. Run next build

Current vs. Expected behavior

Current Behaviour:
Next.js will flag /sitemap.xml as a dynamic route instead of a static one

Expected Behaviour:
Next.js should flag /sitemap.xml as a static route unless explicitly defined to be a dynamic one by the user

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 11 Home Single Language
  Available memory (MB): 32540
  Available CPU cores: 16
Binaries:
  Node: 24.8.0
  npm: 11.5.2
  Yarn: N/A
  pnpm: 10.19.0
Relevant Packages:
  next: 16.0.1-canary.2 // Latest available version is detected (16.0.1-canary.2).
  eslint-config-next: N/A
  react: 19.2.0
  react-dom: 19.2.0
  typescript: 5.9.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Metadata, cacheComponents

Which stage(s) are affected? (Select all that apply)

next build (local)

Additional context

I can also open a PR for the fix

[WarFiN123]

Can I be assigned to this?

[Joshua-hypt]

If you want it to be static, you have to mark it with 'use cache' in a way I suppose

[WarFiN123]

If you want it to be static, you have to mark it with 'use cache' in a way I suppose

The default behavior should be generating it as a static route. Like the robots file or opengraph images.