[Merged by Bors] - feat(AlgebraicGeometry): a quasi-compact cover of a quasi-compact scheme can be refined by a finite affine cover

[chrisflav]

We also show that quasi-compact covers (in an arbitrary universe) of schemes in universe u can be lifted to u-covers.

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• depends on: [Merged by Bors] - feat(CategoryTheory/Sites): various API additions for #34917 #34921

[github-actions]

PR summary c7b39cbff6

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

+ exists_hom
+ instance {S : Scheme.{u}} (𝒰 : PreZeroHypercover S) [QuasiCompactCover 𝒰] :
+ ulift
+ uliftHom

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).

[mathlib-dependent-issues]

This PR/issue depends on:

• [Merged by Bors] - feat(CategoryTheory/Sites): various API additions for #34917 #34921
  By Dependent Issues (🤖). Happy coding!

[joelriou]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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