chore: redefine Nat.div2 Nat.bodd

[astrainfinita]

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This PR continues the work from #13649.

Original PR: #13649

[astrainfinita]

Comments from Original PR #13649

This section contains 2 comment(s) from the original PR, excluding bot comments.

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@urkud (2024-06-09 04:37 UTC):
Please describe how and why did you change the definition(s) in the commit message.

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@eric-wieser (2024-10-20 14:51 UTC):
@FR-vdash-bot, please solve the merge conflicts.

[github-actions]

PR summary de4f458186

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).