fix: typescript 6.0 compatibility

[jasonlyu123]

extracted from #2985. This is the only runtime compatibility problem I found with TypeScript 6.0. Extracted out so we can release this separately.

[changeset-bot]

🦋 Changeset detected

Latest commit: d43d6e9

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
svelte-language-server	Patch
svelte-check	Patch

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[GrygrFlzr]

The original double ternary was already kind of difficult to read, would it be too much to refactor to an IIFE

const factory = (() => {
    if (major === 5 && minor < 3) return createProject50;
    if (major === 5 && minor < 5) return createProject53;
    return createProject55;
})();

Which is probably more friendly to future additions, e.g. a hypothetical

const factory = (() => {
    if (major === 5 && minor < 3) return createProject50;
    if (major === 5 && minor < 5) return createProject53;
    if (major === 5 && minor <= 9) return createProject55;
    return createProject60;
})();

And would have made it easier to spot the initial issue, as it would have been like this:

const factory = (() => {
    if (minor < 3) return createProject50;
    if (minor < 5) return createProject53;
    return createProject55;
    // clearly not checking major
})();

[jasonlyu123]

Tweaked. This might be the last time we touch this 😆. There most likely won't be a new version anyway.