refactor(CategoryTheory): insert missing Functor.op compatibility isomorphisms

[kim-em]

This PR inserts Functor.opId, Functor.opComp and the new Functor.leftOpCompOp where Mathlib currently identifies (F ⋙ G).op with F.op ⋙ G.op, (𝟭 C).op with 𝟭 Cᵒᵖ, or (F ⋙ G.op).leftOp with F.leftOp ⋙ G by unfolding Functor.op, and states the units and counits of Adjunction.op, unop, leftOp and rightOp componentwise rather than as NatTrans.op/NatTrans.unop at a type that only matches after unfolding. The unit and counit of opOpEquivalence are likewise built from components. The affected declarations are opShiftFunctorEquivalence, SimplicialObject.opFunctorCompOpFunctorIso and Limits.exists_eq_isColimitMap_of_preservesColimit_coyoneda.

It is extracted from Paul Reichert's experiment making Functor.comp and Functor.id instance_reducible (master...leanprover-community:mathlib4-nightly-testing:datokrat/functorcomp, discussed at https://leanprover.zulipchat.com/#narrow/channel/113488-general/topic/backward.2EisDefEq.2ErespectTransparency), keeping only the Functor.op fixes; the associator and unitor fixes are in #43566.

🤖 Prepared with Claude Code

[github-actions]

PR summary 312f6cf987

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff (regex)

+ leftOpCompOp

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 312f6cf).

• +11 new declarations
• −8 removed declarations

-CategoryTheory.Adjunction.leftOp_counit
+CategoryTheory.Adjunction.leftOp_counit_app
-CategoryTheory.Adjunction.leftOp_unit
+CategoryTheory.Adjunction.leftOp_unit_app
-CategoryTheory.Adjunction.op_counit
+CategoryTheory.Adjunction.op_counit_app
-CategoryTheory.Adjunction.op_unit
+CategoryTheory.Adjunction.op_unit_app
-CategoryTheory.Adjunction.rightOp_counit
+CategoryTheory.Adjunction.rightOp_counit_app
-CategoryTheory.Adjunction.rightOp_unit
+CategoryTheory.Adjunction.rightOp_unit_app
-CategoryTheory.Adjunction.unop_counit
+CategoryTheory.Adjunction.unop_counit_app
-CategoryTheory.Adjunction.unop_unit
+CategoryTheory.Adjunction.unop_unit_app
+CategoryTheory.Functor.leftOpCompOp
+CategoryTheory.Functor.leftOpCompOp_hom_app
+CategoryTheory.Functor.leftOpCompOp_inv_app

---

Increase in strong tech debt: (relative, absolute) = (0.79, 0.00)

Current number	Change	Type (strong)
backward.defeqAttrib.useBackward	4245	-1
erw	497	1

No changes to weak technical debt.

Current commit 312f6cf987
Reference commit 572e4d091b

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.py 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).