[NDTensorsMetalExt] Fix more scalar indexing issues on Metal

[kmp5VT]

Description

Trying to get Metal up to speed as CUDA is and have it be testable in the NDTensors/test suite.

Fixes #(issue)

Remove scalar indexing but also running into issues with Float64 typing in NDTensors.

• Changing the file names in NDTensors/test to test_filename.jl and writing the loop to go over test_*.jl
• In each test file I am going to add a @safetestset to the beginning of the file and put the using statements in the safetestset section.
• I'll explicitly write which functions are included from each of the modules in all of the test files.
• In files where metal breaks because of eltype issues I will migrate Tensor(...) constructors to Tensor{elt}(...) and loop over eltypes.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (d7167b8) 84.06% compared to head (f6d3e50) 53.94%.

❗ Current head f6d3e50 differs from pull request most recent head a2d569d. Consider uploading reports for the commit a2d569d to get more accurate results

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Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1264       +/-   ##
===========================================
- Coverage   84.06%   53.94%   -30.13%     
===========================================
  Files          99       98        -1     
  Lines        8542     8489       -53     
===========================================
- Hits         7181     4579     -2602     
- Misses       1361     3910     +2549     

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[kmp5VT]

@mtfishman To recap our conversation and as a refresher for me. The notes for changes are as follows

1. Changing the file names in NDTensors/test to test_filename.jl and writing the loop to go over test_*.jl
2. In each test file I am going to add a @safetestset to the beginning of the file and put the using statements in the safetestset section.
3. I'll explicitly write which functions are included from each of the modules in all of the test files.
4. In files where metal breaks because of eltype issues I will migrate Tensor(...) constructors to Tensor{elt}(...) and loop over eltypes.

[kmp5VT]

@mtfishman I believe this is ready for review

[kmp5VT]

@mtfishman I am not sure why these tests are failing. When I test with Julia 1.9 all pass but it looks like theres an issue with sort in julia 1.6 and 1.8. I didn't make any modifications to the code that is failing. To verify I grabbed the last passing version of this branch (tag b56f8a4) and ran ]test NDTensors in julia 1.8 and it also fails in the sort function in blocksparse contraction with the combiner. Do you have any idea what is happening?

[mtfishman]

May be related to JuliaLang/Compat.jl#812 and JuliaLang/julia#52010, sorting tuples was temporarily supporting in Base Julia but then removed.

In places where sort(::Tuple) is failing we can try to change the call to TupleTools.sort(...).

[mtfishman]

Thanks for the quick fix to the tuple sorting issue. I'll merge this so we can register a new version.