pause on debugger for full page reloads in dev

[Rich-Harris]

closes #9284

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[dummdidumm]

Approving, but not merging yet, to see if we can batch something else into a minor release that's a feature.

In general I was wondering if things like this would be better served through some kind of dev time overlay. I don't know how much Vite let's us customize its overlay, and if it's possible to ping back to the dev server here. Maybe it's also our own custom dev time info overlay similar to how NextJS has them. Anyways, these are just nebolous thoughts I thought may fit here.

[Rich-Harris]

Agree. Astro is another example closer to home - they override the vite overlay. There's lots of room for improvement around errors generally