fix: increment version when creating new source in Map.get or Map.has

[paoloricciuti]

Svelte 5 rewrite

Closes #11909

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Latest commit: 017b57b

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[Rich-Harris]

This doesn't really feel like the right solution to me. The reason the test fails without this change seems to be because there's no source initially created by the time #read_all is called — surely we should be populating this.#sources in the constructor?

[paoloricciuti]

This doesn't really feel like the right solution to me. The reason the test fails without this change seems to be because there's no source initially created by the time #read_all is called — surely we should be populating this.#sources in the constructor?

I might be wrong but i think @trueadm specifically created the sources lazily...that's why i went with this solution.

[Rich-Harris]

We can populate it lazily in #read_all but we definitely don't want to invalidate the entire thing on every get or has, that's very expensive