[Merged by Bors] - chore(NumberTheory/RamificationInerta/Basic): split file

[tb65536]

This PR splits off the basic API for ramification index and inertia degree into separate files.

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[github-actions]

PR summary ec3a721d5b

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
27 files Mathlib.NumberTheory.FLT.Three Mathlib.NumberTheory.Height.NumberField Mathlib.NumberTheory.NumberField.AdeleRing Mathlib.NumberTheory.NumberField.ClassNumber Mathlib.NumberTheory.NumberField.Completion.FinitePlace Mathlib.NumberTheory.NumberField.Cyclotomic.Basic Mathlib.NumberTheory.NumberField.Cyclotomic.Ideal Mathlib.NumberTheory.NumberField.Cyclotomic.PID Mathlib.NumberTheory.NumberField.Cyclotomic.Three Mathlib.NumberTheory.NumberField.DedekindZeta Mathlib.NumberTheory.NumberField.Discriminant.Different Mathlib.NumberTheory.NumberField.FinitePlaces Mathlib.NumberTheory.NumberField.Ideal.Asymptotics Mathlib.NumberTheory.NumberField.Ideal.Basic Mathlib.NumberTheory.NumberField.Ideal.KummerDedekind Mathlib.NumberTheory.NumberField.ProductFormula Mathlib.NumberTheory.RamificationInertia.Basic Mathlib.NumberTheory.RamificationInertia.Galois Mathlib.NumberTheory.RamificationInertia.HilbertTheory Mathlib.NumberTheory.RamificationInertia.Unramified Mathlib.RingTheory.DedekindDomain.Different Mathlib.RingTheory.DedekindDomain.Factorization Mathlib.RingTheory.DedekindDomain.FiniteAdeleRing Mathlib.RingTheory.DedekindDomain.LinearDisjoint Mathlib.RingTheory.Ideal.Norm.RelNorm Mathlib.RingTheory.Localization.AtPrime.Extension Mathlib.Topology.Algebra.Ring.Compact	2
Mathlib.NumberTheory.RamificationInertia.Ramification (new file)	1906
Mathlib.NumberTheory.RamificationInertia.Inertia (new file)	1993

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

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).

[erdOne]

Thanks!
maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by erdOne.

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issue_comment, wf_run

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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