feat(CategoryTheory): StructuredArrow c (Comma.fst F G) is equivalent toComma (Under.forget c ⋙ F) G

[javra]

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[github-actions]

PR summary c360858690

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

+ ofCommaFstEquivalence
+ ofCommaFstEquivalenceFunctor
+ ofCommaFstEquivalenceInverse
+ ofCommaSndEquivalence
+ ofCommaSndEquivalenceFunctor
+ ofCommaSndEquivalenceInverse

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).

[joelriou]

Suggested change

	/-- There is a canonical equivalence between the costructured arrow category with codomain `c` on
	the functor `Comma.fst F G : Comma F G ⥤ F` and the comma category over
	`Over.forget c ⋙ F : Over c ⥤ T` and `G`. -/
	/-- There is a canonical equivalence between the structured arrow category with domain `c` on
	the functor `Comma.fst F G : Comma F G ⥤ F` and the comma category over
	`Under.forget c ⋙ F : Under c ⥤ T` and `G`. -/