fix: better missing peer dep error

[Rich-Harris]

per #11578 (comment), the current message isn't very helpful when you have a missing peer dependency

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[dummdidumm]

I'd rather revert the change completely. It would reenable yarn pnp to some extent (not that this argument matters too much tbh), but also letting handle node resolution algorithm handle these cases feels better to me than relying on a runtime lookup. It may also result in breakage where previously a dependency was found somewhere else which it is no longer now, which strictly speaking is a breaking change.
Given that this was only introduced to make Svelte 5 linking a bit easier I'm in favor or reverting.

[Rich-Harris]

Not sure I understand this hypothetical breakage scenario?

Discounting that, we're basically choosing between PnP support and our own sanity. I think you're underestimating just how painful it will be, on an ongoing basis, to develop against multiple versions of peer dependencies. I found it nightmarish. And I really don't care about PnP