Add absent status

[JossyYila]

• Kind: / enhancement /

• Close #462

Description

Change the display of not-found functions to be more user-friendly

Checklist

• [ ] Read the CONTRIBUTING.md guide and:
  • [ ] Use Atomic Commits so each commit gathers a single logical change
  • [ ] Use Conventional Commits regarding commit messages (needed by our release toolchain)
• [ ] Add/update tests
• [ ] Add/update documentation
• [ ] …

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• Read this wiki page
• Make sure the PR has a milestone
• Assign yourself before merging
• We can squash-merge 1-commit PRs (use a header with a conventional-commit type, add a footer with Fix #… if need be)