[Merged by Bors] - feat(Algebra): auxiliary lemmas for flatness over semirings

[alreadydone]

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[github-actions]

PR summary bd84f8e34c

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

+ congr
+ directSumRight_comp_rTensor
+ exists_fg_le_eq_rTensor_subtype
+ exists_fg_le_subset_range_rTensor_inclusion
+ exists_fg_le_subset_range_rTensor_subtype
+ lTensor_comp_cancelBaseChange
+ lmap
+ lmap_apply
+ lmap_injective
+ lmap_lof
+ mapRange_injective
+ of_equiv
+ small
+ tensorProduct_isLocalizedModule

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).

[jcommelin]

Thanks 🎉

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded!

And happy new year! 🎉

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