Generate nupkg for local builds

Prerequisites

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Module

Documentarian, Documentarian.DevX, Documentarian.MarkdownLint, Documentarian.MicrosoftDocs, Documentarian.ModuleAuthor, Documentarian.Vale

Summary

Our local build process currently composes the PowerShell modules into a folder structure resembling a published module. We use those composed folders when we publish releases to the gallery.

It would be even more useful to generate the nupkg locally, so we can include testing (and investigate publishing nightly releases or similar).

Details

Implementation for this process should be to extend the Documentarian.DevX module to support a PackageModule task, which:

• Depends on the ComposeModule task.
• Registers a temporary local PowerShell repository in a well-defined folder.
• Publishes the composed module to the temporary local repository.
• Unregisters the temporary local repository.

We should make sure the output folder for packaged modules is included in the .gitignore definition.

Start by reading the linked ComposeModule.ps1 task and inspecting the Documentarian.DevX module's task structure. Add the PackageModule flow described in the issue, including temporary repository registration and cleanup, and update .gitignore for the packaged-module output; done means local builds produce a usable nupkg without leaving the repository registered.