[Merged by Bors] - feat(CategoryTheory/NatTrans): use to_dual

[JovanGerb]

This PR tags NatTrans with to_dual. The two functor arguments get swapped because the underlying NatTrans.app has its direction swapped.

Translating the naturality field is slightly awkward. We need to define a constant naturality' (analogously to `Category.assoc')

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• depends on: [Merged by Bors] - feat(CategoryTheory/Functor): use @[to_dual] #33237
• depends on: [Merged by Bors] - feat(translate): linter for overwriting existing translations #33777

[github-actions]

PR summary 25d72f3b6b

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

+ NatTrans.naturality'

You can run this locally as follows

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

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

The doc-module for script/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/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).

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[mathlib4-dependent-issues-bot]

This PR/issue depends on:

• [Merged by Bors] - feat(CategoryTheory/Functor): use @[to_dual] #33237
• [Merged by Bors] - feat(translate): linter for overwriting existing translations #33777
  By Dependent Issues (🤖). Happy coding!

[robin-carlier]

Thanks!

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by robin-carlier.

[joelriou]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Post-Build Step
• Lint style
• Build