Show debug-info can be a boolean

[philderbeast]

Fixes #12142. Add boolean as a type and the range of integers accepted. Also moves the GHC-specific details to their own tip-like admonition.

As rendered:

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• Patches conform to the coding conventions.
• Is this a PR that fixes CI? If so, it will need to be backported to older cabal release branches (ask maintainers for directions).

[mergify]

Merge Queue Status

• ✅ Entered queue — 2026-07-25 12:12 UTC · Rule: default · triggered by rule Put pull requests in the rebase+merge queue
• ✅ Checks passed · on draft merge queue: checking master (7ecb16b) and [#12057 + #12149 + #12143] together #12159
• ✅ Merged — 2026-07-26 06:11 UTC · at df6f98b7ce02e9d5fe1abbcb3d6a9fd56fcc78bc · merge

This pull request spent 17 hours 58 minutes 34 seconds in the queue, including 1 hour 52 minutes 14 seconds running CI.

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  • refactor: make Graph.broken return NonEmpty missing deps #12057
  • Show debug-info can be a boolean #12143
  • Use usageAlternatives with v2-clean #12149
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  • refactor: make Graph.broken return NonEmpty missing deps #12057
  • Show debug-info can be a boolean #12143
  • Use usageAlternatives with v2-clean #12149
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