feat: lemmas about Measure.count

[fpvandoorn]

• Also add some gcongr attributes for Real.toENNReal.

Used for Sobolev spaces

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[github-actions]

PR summary d8499b6b7d

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.MeasureTheory.Function.LpSeminorm.Count (new file)	1858

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Declarations diff

+ _root_.Function.Injective.map_count_le
+ _root_.Subsingleton.count_eq_dirac
+ _root_.Unique.count_eq_dirac
+ eLpNorm_count_lt_top
+ eLpNorm_count_lt_top_of_lt
+ eLpNorm_dirac
+ enorm_le_eLpNorm_count

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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Increase in tech debt: (relative, absolute) = (1.00, 0.00)

Current number	Change	Type
10066	1	backward.isDefEq

Current commit 6ee5a9292e
Reference commit d8499b6b7d

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).