chore(Algebra/Order/Hom/Basic): split file by imports

[tb65536]

I ran intro trouble importing Algebra/Order/Hom/Basic into Algebra/Order/BigOperators/Group/Finset (which has assert_not_exists Ring) in order to prove subadditivity for finite sums.

The file Algebra/Order/Hom/Basic is already organized into a basic section, a group norms section, and a ring norms section, so splitting the file along those divisions seemed simplest.

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[github-actions]

PR summary a2b9f4335e

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Algebra.Order.Hom.Basic	274	196	-78 (-28.47%)

Import changes for all files

Files	Import difference
Mathlib.Algebra.Order.Hom.Basic	-78
Mathlib.Algebra.Order.Hom.Lattice	-25
Mathlib.Algebra.Order.Hom.GroupNormClass (new file)	265
Mathlib.Algebra.Order.Hom.RingNormClass (new file)	276

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Declarations diff (regex)

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

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 42c53ff).

• +0 new declarations
• −0 removed declarations

No declaration differences.

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No changes to strong technical debt.
No changes to weak technical debt.

Current commit a2b9f4335e
Reference commit bb6825500b

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.py 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).