Migrate Thrust zip iterators to CUDA equivalents

[PointKernel]

Description

This PR replaces remaining thrust::zip_iterator and thrust::make_zip_iterator usage with CUDA equivalents across cuDF, including C++ tests and benchmarks. This also updates the corresponding iterator includes to use CUDA headers.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

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📝 Walkthrough

Summary by CodeRabbit

• Refactor

  • Standardized GPU processing across analytics, joins, reductions, sorting, strings, and JSON, ORC, and Parquet workflows.
  • Updated iterator utilities while preserving existing results and behavior.

• Bug Fixes

  • Improved Parquet page-index metadata handling and row-mask construction.

• Tests

  • Updated unit tests and utilities to reflect the processing changes.
  • Existing assertions and expected results remain unchanged.

Walkthrough

Changes

CUDA iterator factories replace Thrust equivalents across cuDF benchmarks, algorithms, IO, parsing contracts, joins, reductions, and tests. Parquet metadata handling also adds page-index, offset-cache, and row-mask logic.

CUDA iterator and Parquet metadata migration

Layer / File(s)	Summary
Foundational iterator contracts and algorithms cpp/include/cudf/..., cpp/src/groupby/..., cpp/src/join/..., cpp/src/lists/..., cpp/src/quantiles/..., cpp/src/reductions/..., cpp/src/replace/..., cpp/src/sort/..., cpp/src/strings/...	Internal iterator construction and string-parsing iterator contracts now use CUDA iterator utilities.
Compression, JSON, and text IO paths cpp/src/io/comp/..., cpp/src/io/json/..., cpp/src/io/text/...	Compression, JSON, and text paths replace Thrust iterator factories and adjust related iterator expressions.
Parquet metadata and page-index handling cpp/src/io/parquet/..., cpp/src/io/utilities/...	Parquet metadata code adds page-index presence and range handling, cached column-chunk offsets, offset-index checks, and all-true row-mask construction. Parsing APIs use CUDA zip-iterator parameter types.
Validation and test updates cpp/tests/...	Tests and assertion helpers adopt CUDA iterator headers and factories without changing expected results.

Estimated code review effort: 4 (Complex) | ~45 minutes

Possibly related PRs

• rapidsai/cudf#23338: Both PRs migrate Thrust iterator factories to CUDA equivalents in overlapping benchmark and JSON paths.

Suggested reviewers: mythrocks, mhaseeb123, vuule, bdice

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 20.34% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the migration from Thrust zip iterators to CUDA equivalents across the codebase.
Description check	✅ Passed	The description directly explains the iterator migration and related include updates described in the changeset.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[PointKernel]

/merge