Separate more cuda code

[RAMitchell]

No description provided.

[Copilot]

Pull Request Overview

This pull request separates CUDA-specific code by moving GPU implementations to dedicated .cu files, aligning with CUDA compilation requirements. The PR extracts GPU variants and CUDA-specific functions from mixed .cpp files into separate CUDA compilation units.

Key changes include:

• Moved GPU implementations from .cpp files to new .cu files for proper CUDA compilation
• Updated class definitions to use static member functions with forward declarations in headers
• Removed unused variables from test files

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
cpp/tests/test_task.cpp	Renamed function from get_library() to get_test_library()
cpp/tests/test_groupby_aggregation.cpp	Removed unused CUDF aggregation kind variables
cpp/src/join.cu	New file containing GPU variant and CUDA-specific join functions
cpp/src/join.cpp	Removed GPU variant and CUDA includes, kept CPU implementation
cpp/src/groupby_aggregation.cu	New file containing GPU variant and CUDA-specific aggregation functions
cpp/src/groupby_aggregation.cpp	Removed GPU variant and CUDA includes, kept CPU implementation
cpp/src/filling.cu	New file containing GPU variant for sequence task
cpp/src/filling.cpp	Removed GPU variant and CUDA includes, kept CPU implementation
cpp/include/legate_dataframe/join.hpp	Added task class definition and function declarations
cpp/include/legate_dataframe/groupby_aggregation.hpp	Added task class definition and removed CUDF includes
cpp/include/legate_dataframe/filling.hpp	Added task class definition and updated documentation
cpp/include/legate_dataframe/csv.hpp	Added CPU variant options constant

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[seberg]

Looks good, thanks for including the csv CPU_VARIANT_OPTIONS fix!