feat(Algebra): forgetful lemmas for `map` and `comap` on substructures

[artie2000]

• Standardise the form of forgetful lemmas for map and comap (ie, (co)map_toSubfoo)
• Add missing lemmas of this form
• Mark all such lemmas as simp

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• [ ] depends on: #21031

[github-actions[bot]]

PR summary 3ea6690c34

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ comap_toAddSubgroup + comap_toNonUnitalSubsemiring + comap_toSubalgebra + comap_toSubsemiring + map_toAddSubmonoid + map_toSubmonoid + map_toSubsemiring ++ comap_toAddSubmonoid ++ comap_toSubmodule -++ comap_toSubmonoid

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).

[mathlib4-dependent-issues-bot]

This PR/issue depends on:

• leanprover-community/mathlib4#21031 By Dependent Issues (🤖). Happy coding!