[Merged by Bors] - doc(Algebra/Module/Projective): remove TODOs

[abeldonate]

Remove the TODO list, since the have already been implemented on an instance.

[github-actions]

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[github-actions]

PR summary 20c3a51ac9

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

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.

---

No changes to strong technical debt.

No changes to weak technical debt.

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[robin-carlier]

Thanks!

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by robin-carlier.

[riccardobrasca]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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• ci (staging) / Post-CI job

[vlad902]

Which instance? loogle doesn't find anything for DirectSum, Module.Projective

[vlad902]

i.e. the following fails for me on main

import Mathlib

variable (R : Type) [CommRing R] {ι : Type v} (M : ι → Type) [(i : ι) → AddCommMonoid (M i)] [(i : ι) → Module R (M i)] [∀ (i : ι), Module.Projective R (M i)]

#synth Module.Projective R (DirectSum ι (fun (i : ι) => M i))

[vlad902]

#39764

[abeldonate]

I the file Algebra/Module/Projective, i see the following instances:

instance [Projective R P] [Projective R Q] : Projective R (P × Q)
instance [h : ∀ i : ι, Projective R (A i)] : Projective R (Π₀ i, A i)

around line 138