fix: navigate without reloading for links with a target attribute that will display in the current browsing context

[eltigerchino]

fixes #13162

This PR corrects the external link condition by also checking the target type instead of just the presence of the target attribute. Now links that open in the same browsing context won't be treated as external.

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🦋 Changeset detected

Latest commit: 166d9e6

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[Rich-Harris]

preview: https://svelte-dev-git-preview-kit-13165-svelte.vercel.app/

this is an automated message

[dummdidumm]

should it be this instead? We can't know for certain if the browsing context will be the same as ours for _top etc

Suggested change

	target === '_blank' ||
	(target || '_self') !== '_self' ||

[eltigerchino]

Would location.ancestorOrigins work to check if there are no parents/ancestors? https://developer.mozilla.org/en-US/docs/Web/API/Location/ancestorOrigins

If there is a way to check for parent browsing contexts then the page wouldn't need to reload when these values should behave similar to _self.

_parent: The parent browsing context of the current one. If no parent, behaves as _self.

_top: The topmost browsing context. To be specific, this means the "highest" context that's an ancestor of the current one. If no ancestors, behaves as _self.

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/a#target

[Conduitry]

Using target=_self as a way to indicate to an SPA framework that a given link should be treated normally rather than being intercepted predates SvelteKit. There are a number of frameworks that work this way. It may not have ever been documented in SK's docs - and there may be other official SK-specific ways of doing this - but I don't think we can just remove it. At the very least, removing this should be a breaking change.