[documentation-writing-alignment] Resolve the Test-PSModule Run_Path caller contract #575

Context and request

Callers can set the public Run_Path input on .github/actions/Test-PSModule/action.yml, but the action does not pass that input to its runner. The native-help/prose delivery #558 cannot change this interface or runtime wiring.

Evidence and expected result

At 64ffb1d87f86bd5d487891fdb140b78385a00531, inputs.Run_Path describes directories or files for test discovery. In the action's Invoke-Pester step, with.Run_Path is always ${{ steps.paths.outputs.CodePath }} rather than ${{ inputs.Run_Path }}. .github/actions/Test-PSModule/src/main.ps1 computes CodePath from Settings and the module/source layout; it does not read the public Run_Path input. #570 preserves this wiring and its values.

Acceptance criteria:

• The supported meaning of Run_Path is explicit and matches the runner configuration.
• A non-default caller value has the documented effect, or a deliberate compatibility decision removes or replaces the unused input.
• Source-code and built-module framework tests still receive the paths they require.
• Default behavior remains unchanged unless an explicit compatibility decision authorizes a change.
• Documentation states the delivered behavior and includes the required caller action, if any.

Technical decisions

Refine the intended contract before implementation. The present CodePath forwarding may serve the framework test container, so do not replace it with caller input without tracing PSModule/Invoke-Pester and the framework container data contract. Keep this behavior work separate from the prose-only delivery. No implementation option is selected by this report.

Implementation plan

• Trace Run_Path, Path, and container data through Test-PSModule and its pinned Invoke-Pester action.
• Choose the supported caller contract and record its compatibility impact before implementation.
• Add a failing narrow caller-value test and default source/module-path regression checks.
• Implement the selected contract and update the action description in a focused draft PR.
• Verify non-default and omitted inputs, both Settings values, and the runner configuration.