feat(Algebra/Category): pushforward of quasi-coherent sheafs

[chrisflav]

We show that the pushforward of a quasi-coherent sheaf along a continuous and cocontinuous functor is quasi-coherent, if it preserves the unit.

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[github-actions]

PR summary 8a4ee08205

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 (regex)

+ CoverPreserving.of_comp_of_isCocontinuous
+ QuasicoherentData.pushforward
+ instance {D : Type*} [Category* D] {J : GrothendieckTopology C} {K : GrothendieckTopology D}
+ instance {X Y : C} (f : X ⟶ Y) [HasPullbacksAlong f] : (Over.map f).IsLeftAdjoint
+ instance {X Y : C} (f : X ⟶ Y) [HasPullbacksAlong f] : (Over.pullback f).IsRightAdjoint
+ isLeftAdjoint_pushforward_of_isIso
+ isQuasicoherent_over
+ isQuasicoherent_pushforward
+ isQuasicoherent_pushforward_of_isLeftAdjoint
+ sieve₀_map

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 8a4ee08).

• +12 new declarations
• −0 removed declarations

+CategoryTheory.CoverPreserving.of_comp_of_isCocontinuous
+CategoryTheory.GrothendieckTopology.instIsContinuousOverCompObjPostMapOver
+CategoryTheory.Over.instIsLeftAdjointMapOfHasPullbacksAlong
+CategoryTheory.Over.instIsRightAdjointPullback
+CategoryTheory.PreOneHypercover.sieve₀_map
+SheafOfModules.QuasicoherentData.pushforward
+SheafOfModules.QuasicoherentData.pushforward_I
+SheafOfModules.QuasicoherentData.pushforward_X
+SheafOfModules.isLeftAdjoint_pushforward_of_isIso
+SheafOfModules.isQuasicoherent_over
+SheafOfModules.isQuasicoherent_pushforward
+SheafOfModules.isQuasicoherent_pushforward_of_isLeftAdjoint

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit 8a4ee08205
Reference commit 530008da0e

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.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).