[libcu++] Use cccl runtime in thrust tests pt 5

[pciolkosz]

#2800 pt 5

[coderabbitai]

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Run ID: 460dbf7f-0953-4536-b2ea-e17f20d0194c

📥 Commits

Reviewing files that changed from the base of the PR and between aeaa386 and 7795734.

📒 Files selected for processing (4)

• thrust/testing/cuda/cccl_runtime_test_helper.cuh
• thrust/testing/cuda/fill.cu
• thrust/testing/cuda/sequence.cu
• thrust/testing/cuda/uninitialized_fill.cu

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📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes
  • Improved CUDA test validation across fill, sequence, and uninitialized-fill operations.
  • Ensured comparisons correctly support buffers containing types other than int.
  • Improved CUDA stream handling and result verification for more reliable test coverage.

Walkthrough

Changes

CUDA runtime test migration

Layer / File(s)	Summary
Runtime assertion type alignment thrust/testing/cuda/cccl_runtime_test_helper.cuh	Host-side assertion storage now uses the buffer’s value type.
Fill test execution migration thrust/testing/cuda/fill.cu	Device and stream tests use functor kernels, CCCL buffers, cuda::stream, and runtime assertions.
Sequence test execution migration thrust/testing/cuda/sequence.cu	Sequence tests replace raw kernels and manual stream management with cuda::launch, CCCL buffers, and stream-based assertions.
Uninitialized-fill test execution migration thrust/testing/cuda/uninitialized_fill.cu	Uninitialized-fill tests use functor kernels, CCCL buffers, stream synchronization, and runtime assertions, including returned-iterator validation.

Suggested reviewers: ericniebler, caugonnet, davebayer, bernhardmgruber

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