feat: Set.prod_image_left

[vihdzp]

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Downstreamed from the CGT repo.

[github-actions]

PR summary 8aa3ccd118

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Data.Set.Operations	106	107	+1 (+0.94%)

Import changes for all files

Files	Import difference
12 files Mathlib.Data.List.SplitLengths Mathlib.Data.Set.Notation Mathlib.Data.Set.Operations Mathlib.Data.Set.Opposite Mathlib.Lean.Expr.ExtraRecognizers Mathlib.Order.Iterate Mathlib.Order.Lattice Mathlib.Order.MinMax Mathlib.Order.Monotone.Basic Mathlib.Order.Monotone.Defs Mathlib.Order.Monotone.Monovary Mathlib.Order.SetNotation	1

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Declarations diff

+ prod_image_left
+ prod_image_right

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).