feat: add fixStacktrace option to ssrLoadModule

[benmccann]

Description

Closes #7046

Additional context

We've gotten a number of bug reports in SvelteKit about stack traces being incorrect. It turns out that's because Vite fixes the stack traces and then we fix them again. While conceptually we should be able to address this purely in our own code, in practice it's been quite difficult given the way our code is currently structured and the number of different places we call ssrLoadModule. We'd like to just be able to wrap all the code in a single try / catch, but without this feature would need to break it into about fifteen different blocks across different classes.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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• Read the Contributing Guidelines.
• Read the Pull Request Guidelines and follow the Commit Convention.
• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
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• Ideally, include relevant tests that fail without this PR but pass with it.

[patak-dev]

Interesting that an unused isolated param was there. This looks good to me, I've added it for discussion with the team in our next meeting. ( edit: it was already there :) )

[patak-dev]

We discussed this PR today with the team and we think it is good to go forward with it 👍🏼