feat(Header): Allow opening and closing to toggle the Mega Menu

[VincentSmedinga]

Describe the pull request

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What

Allows a parent component to open or close the Header.

Why

The Header should close after clicking a link in the Mega Menu.

How

• Rename the local state variable from open to isOpen
• Add an open prop and an onClose callback

Checklist

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• Add or update unit tests
• Add or update documentation
• Add or update stories
• Add or update exports in index.* files
• Start the PR title with a Conventional Commit prefix, as explained here.

Additional notes

• n/a

[VincentSmedinga]

We decided this is not a responsibility of the design system but of the application framework that changes the browser’s default behavior.

We resolved this in our Prototypes application with a Next.js Template.