Python: Move sample validation script from samples/ to scripts/

[TaoChenOSU]

Motivation and Context

We need to keep the samples/ dir as clean as possible as that's our customer landing point to the repo.

Description

Move the sample validation scripts from samples/ to scripts/

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[Copilot]

Pull request overview

Relocates the Python sample validation tooling into python/scripts/ to keep python/samples/ focused on customer-facing sample content, and updates CI + imports to use the new module name/location.

Changes:

• Renames/re-homes the validation package from _sample_validation to sample_validation under python/scripts/.
• Updates internal imports and CLI docs to reference sample_validation.
• Updates the python-sample-validation GitHub Actions workflow to run from python/scripts and upload reports from the new location.

Reviewed changes

Copilot reviewed 9 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
python/scripts/sample_validation/workflow.py	Updates workflow composition imports to sample_validation.*.
python/scripts/sample_validation/run_dynamic_validation_workflow_executor.py	Updates imports and formatting after package move.
python/scripts/sample_validation/report.py	Updates model imports and formatting.
python/scripts/sample_validation/models.py	Introduces shared datamodels for the validation pipeline in the new location.
python/scripts/sample_validation/discovery.py	Updates imports to new models module and minor formatting.
python/scripts/sample_validation/create_dynamic_workflow_executor.py	Updates imports from renamed package and formatting.
python/scripts/sample_validation/const.py	Adds constant module in the new package location.
python/scripts/sample_validation/main.py	Updates CLI usage/docs and path resolution after move.
python/scripts/sample_validation/init.py	Updates package exports/imports to new module name.
python/scripts/sample_validation/README.md	Updates documentation to reflect new scripts/sample_validation location and module name.
.github/workflows/python-sample-validation.yml	Runs validation from python/scripts and updates artifact path + OpenAI var names.

Comments suppressed due to low confidence (3)

python/scripts/sample_validation/README.md:118

• The README still documents --output-dir defaulting to ./_sample_validation/reports, but the CLI default is now ./sample_validation/reports (and the workflow uploads from python/scripts/sample_validation/reports). Please update the documented default so it matches the current CLI behavior/location.
  python/scripts/sample_validation/README.md:106
• The usage examples run uv run python -m sample_validation, but sample_validation/ lives under python/scripts/ and python/scripts isn’t a package. Unless the user cds into python/scripts (as the CI workflow does), python -m sample_validation won’t be importable. Consider updating the README usage section to include cd scripts (from python/) or otherwise clarify the required working directory/PYTHONPATH.
  python/scripts/sample_validation/main.py:57
• --output-dir now defaults to ./sample_validation/reports, but later the code builds the path as samples_dir / args.output_dir, which will put reports under python/samples/sample_validation/reports (and won’t match the GitHub Actions artifact path under python/scripts/...). Consider resolving args.output_dir relative to the current working directory or python_root instead of samples_dir so reports are saved under python/scripts/sample_validation/reports by default.