Refactor & Add polyfills to JS SDK#1

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MulverineX wants to merge 4 commits intoMoosync:mainfrom

MulverineX:main

Commits on Apr 4, 2025

Commits on Apr 5, 2025

Clean up polyfills
MulverineX
committed

Commits on Apr 8, 2025

Polyfill types are working, except for Set methods
MulverineX
committed