feat(Tactic): automatic positivity attribute

[BoltonBailey]

This PR makes an attribute that can be applied directly to lemmas to have them be used by positivity, without additional metaprogramming.

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[github-actions]

PR summary f96958cdab

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
../mathlib-ci/scripts/pr_summary/import_trans_difference.sh all
There are 3829 files with changed transitive imports taking up over 178439 characters: this is too many to display!
You can run this locally from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

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Declarations diff (regex)

+ AutoEntry
+ AutoRel
+ AutoRel.toStrictness
+ applyAutoLemma
+ double
+ double_pos
+ evalAutoPositivityLemmas
+ isZeroExpr
+ nat_sqrt_pos_of_pos
+ parseConcl?
- evalIte

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean -- pending)

Computed after the build finishes.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit f96958cdab
Reference commit f041774a2d

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/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).