fix(components): LinkToExternal

[aklkv]

📌 Summary

Today we are referencing <LinkToExternal/> component and in the many cases it doesn't exists unless consumer has ember-engines as dependancy. In the embroider/vite world all components are evaluated at the build time and needs to resolve correct dependancy. If we were to run hds embroider/vite today it would result in an error about unresolved LinkToExternal component. In order to make this behaviour more controlled we are encapsulating requirements for ember-engines to be explicitly required only in situation when we pass @isRouteExternal as true in which case we do our check for required dependancy resigne component instance or through an error.

Shipping ember-engines is not an option for a couple of reasons:

• it has very interesting v1 era requirements which are impossible to satisfy in addon structure (nor should we)
• it is consumer land dependancy and we should leverage this tacktics of not locking users to our version and letting consumer provide own copy only in situation when it's needed. I can see other optimizations in similar fashion but this is the most pressing one at the moment

🛠️ Detailed description

📸 Screenshots

🔗 External links

Jira ticket: HDS-XXX
Figma file: [if it applies]

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👀 Component checklist

• Percy was checked for any visual regression
• A changelog entry was added via Changesets if needed (see templates here)

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📦 RC Packages Published

Latest commit: 8bab8ed

Published 1 packages

@hashicorp/design-system-components@4.19.0-rc-20250422072018

yarn up -C @hashicorp/design-system-components@rc

[aklkv]

superseded by #2838