Spec.nativeToScVal does not handle scSpecTypeVal for raw JS types

[chadoh]

Describe the bug
Spec.nativeToScVal has no handling for raw JS values (string, number, boolean) when the target Soroban type is scSpecTypeVal (value 0).

What version are you on?
Check yarn.lock or package-lock.json to find out precisely what version of the SDK you're running.

v15

See patch to fix this at https://github.com/Consulting-Manao/tansu/pull/174/changes#diff-cb99254b7560e36159f05b4c9f70b9ea3c324e14c267e09eedb6f3b5c52dd5ad

To Reproduce
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2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
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Additional context
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[Shadow-MMN]

I am done with the tests for Tansu . Can this be assigned to me please.