[Merged by Bors] - feat(Analysis/Hermitian): more lemma to convert between IsHermitian and IsSymmetric

[wwylele]

Separated from #37325

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[github-actions]

PR summary 1a37cd3c8e

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Analysis.Matrix.Hermitian	2132	2145	+13 (+0.61%)

Import changes for all files

Files	Import difference
Mathlib.Analysis.Matrix.Hermitian	13

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Declarations diff

+ LinearMap.isHermitian_toMatrix_iff
+ isSymmetric_toEuclideanLin_iff
+ isSymmetric_toLin_iff

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).

[j-loreaux]

Thanks!

bors d+

[mathlib-bors]

✌️ wwylele can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[wwylele]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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• ci (staging) / Lint style