[Merged by Bors] - feat(Projectivization/Colinear): Define colinearity for points in projective spaces

[Whysoserioushah]

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• depends on: [Merged by Bors] - feat(Projectivization/Independence): add lemma about independence #39778

[github-actions]

PR summary 28f437dee4

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.LinearAlgebra.Projectivization.Collinear (new file)	1383

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Declarations diff

+ IsCollinear
+ IsCollinear_iff
+ IsCollinear_iff_rank
+ bot_coe
+ finrank_le_iff_rank_le
+ finrank_lt_iff_rank_lt
+ isCollinear_empty
+ isCollinear_of_card_eq_two
+ isCollinear_pair
+ isCollinear_singleton'
+ isCollinear_subset
+ isCollinear_subsingleton
+ line_unique
+ line_unique'

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.

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No changes to strong technical debt.

No changes to weak technical debt.

[mathlib-dependent-issues]

This PR/issue depends on:

• [Merged by Bors] - feat(Projectivization/Independence): add lemma about independence #39778
  By Dependent Issues (🤖). Happy coding!

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• ci (staging) / Lint style
• ci (staging) / Post-Build Step
• ci (staging) / Build
• ci (staging) / Post-CI job