Fix types under autotune flag

[laggui]

Checklist

• Confirmed that run-checks all script has been executed.

Changes

• Fixed visibility of types / functions only available with "autotune" feature (and some incorrect names)
• Propagate autotune feature flag to burn-cuda and burn-hip (when using default-features = false, enabling autotune would only work for wgpu)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.57%. Comparing base (fae641f) to head (f14e126).
Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2750      +/-   ##
==========================================
+ Coverage   83.56%   83.57%   +0.01%     
==========================================
  Files         824      824              
  Lines      108465   108453      -12     
==========================================
+ Hits        90638    90639       +1     
+ Misses      17827    17814      -13     

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