[Merged by Bors] - feat(Combinatorics/SimpleGraphs): generalize SimpleGraph.map to any function

[vbeffara]

The point is to be able to use map to define graph contractions. Added the injectivity assumption where needed.

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[github-actions]

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[github-actions]

PR summary 80f4a5fc04

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

+ map_adj'

You can run this locally as follows

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

---

No changes to technical debt.

You can run this locally as

./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).

[YaelDillies]

Looks good!

maintainer merge

[github-actions]

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

[SnirBroshi]

Thanks for doing this!

[ocfnash]

Thanks!

bors d+

[ocfnash]

Suggested change

	{ f with map_rel_iff' := by {
	rw [Equiv.coe_toEmbedding]
	grind [Equiv.apply_eq_iff_eq, map_adj', Adj.ne]
	} }
	{ f with map_rel_iff' := by aesop (add simp map_adj') }

[mathlib-bors]

✌️ vbeffara can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[vbeffara]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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