feat(LinearAlgebra/AffineSubspace): define the range of an AffineMap

[ooovi]

This PR adds the range of affine maps and provides some API, following LinearMap.range.

AI disclosure: I used LLMs for library search and code review.

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[github-actions]

PR summary cdfce12812

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.LinearAlgebra.AffineSpace.AffineSubspace.Range (new file)	1131

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Declarations diff (regex)

+ coe_range
+ injective_rangeRestrict_iff
+ instNonemptyRange
+ mem_range
+ mem_range_self
+ range
+ rangeRestrict
+ range_direction_eq_linear_range
+ range_eq_map_top
+ range_id
+ range_rangeRestrict
+ surjective_rangeRestrict

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 cdfce12).

• +12 new declarations
• −0 removed declarations

+AffineMap.coe_range
+AffineMap.injective_rangeRestrict_iff
+AffineMap.instNonemptyRange
+AffineMap.mem_range
+AffineMap.mem_range_self
+AffineMap.range
+AffineMap.rangeRestrict
+AffineMap.range_direction_eq_linear_range
+AffineMap.range_eq_map_top
+AffineMap.range_id
+AffineMap.range_rangeRestrict
+AffineMap.surjective_rangeRestrict

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No changes to strong technical debt.

Increase in weak tech debt: (relative, absolute) = (1.00, 0.00)

Current number	Change	Type (weak)
exposed public sections	5060	1

Current commit cdfce12812
Reference commit ebec2b1d5b

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).