[Merged by Bors] - feat(Data/Finsupp/Order): add lemma Finsupp.single_le_sum

[MichaelStollBayreuth]

This adds an API lemma for Finsupp that turned out to be useful in Heights.

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[github-actions]

PR summary 2598404fe9

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

+ single_eval_le_sum
+ single_le_sum

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 scripts/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).

[Ruben-VandeVelde]

Is there a multiplicative version for this?

[MichaelStollBayreuth]

I don't think Finsupp has a multiplicative version (at least, it is defined directly without using to_additive, and #check ℕ →₁ ℕ gives an error).

[MichaelStollBayreuth]

@faenuccio Do you think this is ready to be merged now?

[faenuccio]

@faenuccio Do you think this is ready to be merged now?

Yes, thanks!

[faenuccio]

maintainer merge

[github-actions]

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

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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