feat: vector measures associated to functions of bounded variation

[sgouezel]

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[github-actions]

PR summary 721b21cf2b

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.test (new file)	1

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Declarations diff

+ Dense.lipschitzWith_extend
+ MeasuredSets
+ MeasuredSets.continuous_measure
+ MeasuredSets.edist_def
+ enorm_mul_le_of_le'
+ enorm_mul₃_le'
+ enorm_mul₄_le'
+ exists_extension
+ instance : PseudoEMetricSpace (MeasuredSets μ)
+ instance : SetLike (MeasuredSets μ) α
+ norm_mul₄_le'
+ symmDiff_union_subset
+ union_symmDiff_subset
+ union_symmDiff_union_subset

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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Increase in tech debt: (relative, absolute) = (1.00, 0.17)

Current number	Change	Type
6	1	large files

Current commit 523f05d29b
Reference commit 721b21cf2b

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).