[Merged by Bors] - chore(NumberField): create directory Cyclotomic and move relevant files there

[xroblot]

Create the directory NumberTheory/NumberField/Cyclotomic and move there the files concerning cyclotomic fields over ℚ.

Deprecated modules files are added in #30583

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[github-actions]

PR summary c48ea032ed

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.NumberTheory.Cyclotomic.PID	-3028
Mathlib.NumberTheory.Cyclotomic.Three	-3010
Mathlib.NumberTheory.Cyclotomic.Embeddings	-2859
Mathlib.NumberTheory.Cyclotomic.Rat	-2520
Mathlib.NumberTheory.NumberField.Cyclotomic.Basic	2520
Mathlib.NumberTheory.NumberField.Cyclotomic.Embeddings	2859
Mathlib.NumberTheory.NumberField.Cyclotomic.Three	3010
Mathlib.NumberTheory.NumberField.Cyclotomic.PID	3028

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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/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.

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No changes to technical debt.

You can run this locally as

./scripts/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).

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note: file Mathlib/NumberTheory/Cyclotomic/Embeddings.lean` was renamed to `Mathlib/NumberTheory/NumberField/Cyclotomic/Embeddings.lean without a module deprecation
Please create a follow-up pull request adding one. Thanks!

note: file Mathlib/NumberTheory/Cyclotomic/Three.lean` was renamed to `Mathlib/NumberTheory/NumberField/Cyclotomic/Three.lean without a module deprecation
Please create a follow-up pull request adding one. Thanks!

note: file Mathlib/NumberTheory/Cyclotomic/PID.lean` was renamed to `Mathlib/NumberTheory/NumberField/Cyclotomic/PID.lean without a module deprecation
Please create a follow-up pull request adding one. Thanks!

note: file Mathlib/NumberTheory/Cyclotomic/Rat.lean` was renamed to `Mathlib/NumberTheory/NumberField/Cyclotomic/Basic.lean without a module deprecation
Please create a follow-up pull request adding one. Thanks!

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

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