[Chore] Add multi stage conv

[wingertge]

Pull Request Template

Checklist

• Confirmed that run-checks all script has been executed.
• Made sure the book is up to date with changes in this PR.

Related Issues/PRs

Adds new algorithm from tracel-ai/cubecl#602 to autotune

Changes

Adds the new multi-stage convolution algorithm to autotuned conv2d.

Testing

All tests pass with the new algorithm enabled.

[laggui]

Was going to say it's missing the correct cubecl rev, but looks like it was already updated to a recent commit 😄

[codecov]

Codecov Report

Attention: Patch coverage is 59.09091% with 9 lines in your changes missing coverage. Please review.

Project coverage is 81.10%. Comparing base (eaf3160) to head (e38dd2c).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/burn-cubecl-fusion/src/shared/io.rs	10.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3105      +/-   ##
==========================================
+ Coverage   81.08%   81.10%   +0.01%     
==========================================
  Files         816      816              
  Lines      117376   117377       +1     
==========================================
+ Hits        95180    95194      +14     
+ Misses      22196    22183      -13     

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