[Merged by Bors] - feat(AlgebraicGeometry): define integral morphisms

[erdOne]

also shows that finite = integral + locally of finite type and closed immersion = finte + mono

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[github-actions]

PR summary 2e3396daa1

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.RingTheory.RingHom.Integral	1483	1499	+16 (+1.08%)
Mathlib.AlgebraicGeometry.Morphisms.Finite	1820	1833	+13 (+0.71%)

Import changes for all files

Files	Import difference
Mathlib.AlgebraicGeometry.Morphisms.Finite	13
Mathlib.RingTheory.RingHom.Integral	16
Mathlib.AlgebraicGeometry.Morphisms.Integral	1830

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Declarations diff

+ IsIntegralHom
+ _root_.AlgebraicGeometry.IsClosedImmersion.eq_isFinite_inf_mono
+ _root_.AlgebraicGeometry.IsClosedImmersion.iff_isFinite_and_mono
+ eq_inf
+ hasAffineProperty
+ iff_isIntegralHom_and_locallyOfFiniteType
+ instance (priority := 900) [IsFinite f] : IsIntegralHom f
+ instance (priority := 900) [hf : IsFinite f] : LocallyOfFiniteType f
+ instance (priority := 900) {X Y : Scheme} (f : X ⟶ Y) [IsClosedImmersion f] : IsFinite f
+ instance : ContainsIdentities @IsIntegralHom
+ instance : IsMultiplicative @IsIntegralHom
+ instance : IsStableUnderBaseChange @IsIntegralHom
+ instance : IsStableUnderComposition @IsIntegralHom
+ isIntegral_ofLocalizationSpan
- instance (priority := 900) [hf : IsFinite f] : LocallyOfFiniteType f := by

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).

[chrisflav]

Thanks!

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by chrisflav.

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

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