fix: ensure inserted code is preserved during migration

[paoloricciuti]

Svelte 5 rewrite

Closes #13615

Not super happy with this but didn't find a better way. The problem is that the code assumes that we will remove one character in case of \n or 2 in case of \r\n. However based on how MagicString works if we inserted a character at that position before removing at that position will also remove the inserted character.

To fix this i snip the already transformed string to take a look at what we are removing and i trim it...any character left is added to the remove starting point.

I don't think we can find a situation where we have a character after the carriage so this should work.

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🦋 Changeset detected

Latest commit: 9282397

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[dummdidumm]

If this is about append/prepend stuff being removed, use update(start, end, '') instead, which preserves those

[paoloricciuti]

If this is about append/prepend stuff being removed, use update(start, end, '') instead, which preserves those

Uh interesting let me try

[paoloricciuti]

If this is about append/prepend stuff being removed, use update(start, end, '') instead, which preserves those

Flawless...thanks.