feat(CategoryTheory/Sites): under certain conditions, cover preserving functors preserve 1-hypercovers

[joelriou]

---

• [ ] depends on: #13004
• [ ] depends on: #13011
• [ ] depends on: #13012

[github-actions[bot]]

PR summary 66ccdd3e07

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

+ CoverPreserving.preservesOneHypercovers_of_downward_closed + CoverPreserving.preservesOneHypercovers_of_representablyFlat + functorPushforward_ofArrows + instance {X : C} {Y : Over X} (E : (J.over X).OneHypercover Y) : + le_map_sieve₁ + map_sieve₀

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>

[leanprover-community-mathlib4-bot]

This PR/issue depends on:

• ~~leanprover-community/mathlib4#13004~~
• ~~leanprover-community/mathlib4#13011~~
• ~~leanprover-community/mathlib4#13012~~ By Dependent Issues (🤖). Happy coding!