feat(Combinatorics/Additive): link Freiman homs and Freiman isos tighter

[b-mehta]

Some work I had lying around in a forgotten branch, recently resurrected.

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[github-actions]

PR summary 9519868b83

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

+ InjOn.left_prodMk
+ InjOn.right_prodMk
+ IsMulFreimanHom.fst
+ IsMulFreimanHom.prodMk
+ IsMulFreimanHom.prod_apply
+ IsMulFreimanHom.snd
+ IsMulFreimanHom.toIsMulFreimanIso
+ IsMulFreimanIso.isMulFreimanIso_invFunOn
+ IsMulFreimanIso.symm
+ LeftInvOn.left_prodMk
+ LeftInvOn.right_prodMk
+ MapsTo.prodMk
+ MulHomClass.isMulFreimanHom
+ card_eq_succ
+ isMulFreimanHom_antitone
+ length_eq_succ_iff
+ surjOn_fst
+ surjOn_fst_iff
+ surjOn_snd
+ surjOn_snd_iff
- MonoidHomClass.isMulFreimanHom

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.

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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).