Sorry-free polynomial FLT

[jcpaik]

Another progress on polynomial FLT #18882

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[github-actions]

PR summary de6f58a8e9

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.NumberTheory.FLT.Polynomial	1179

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Declarations diff

+ Polynomial.flt'
+ Polynomial.flt_catalan
+ Polynomial.flt_catalan_aux
+ fermatLastTheoremPolynomial
+ radical_isUnit_eq
+ radical_isUnit_mul_left
+ radical_isUnit_mul_right
- radical_mul_unit
- radical_unit_eq_one
- radical_unit_mul

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.