feat(AlgebraicGeometry/IdealSheaf/IrreducibleComponent): subscheme structure on an irreducible component

[tb65536]

This PR defines the subscheme structure on an irreducible component of a Noetherian scheme. See the module docstring for more details on this.

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[github-actions]

PR summary 56d691c029

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.AlgebraicGeometry.IdealSheaf.IrreducibleComponent (new file)	2286

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Declarations diff

+ instance : IrreducibleSpace (X.irreducibleComponent Z hZ)
+ instance : IsClosedImmersion (X.irreducibleComponentι Z hZ)
+ instance [IrreducibleSpace X] : CategoryTheory.IsIso (X.irreducibleComponentι Z hZ) := by
+ irreducibleComponent
+ irreducibleComponentIdeal
+ irreducibleComponentι
+ irreducibleComponentι_apply

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).

[erdOne]

It is probably useful to have an IrreducibleSpace instance on this.