Add .npmrc with default registry configuration

[plemarquand]

Description

This is useful when a users default registry is not the public one

Tasks

• Required tests have been written
• Documentation has been updated
• Added an entry to CHANGELOG.md if applicable

[Copilot]

Pull Request Overview

This PR adds a default npm registry configuration file (.npmrc) to ensure the project uses the public npm registry, which is helpful when users have a different default registry configured.

• Adds .npmrc file with explicit public registry configuration

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[plemarquand]

Must have hit that button by accident. Thanks for your detailed review, copilot.