fix: recover scroll position on reload of SPAs

[timhallmann]

If SSR is disabled, the scroll position won't be restored when the page is reloaded. This happens because scrollTo is called before the page is rendered, meaning the target scroll position does not yet exist. Conversely, when SSR is enabled, scrollTo works as expected since the page is already rendered, and the scroll position exists.

I wasn't sure if the order of scrolling and hydrating mattered, so I did not move the scrollTo behind the if (hydrate) block.

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