Can add sideEffects false to package.json

[skywalker512]

If i use @udecode/plate to import, because packages like @udecode/plate-juice don't have sideEffects false in package.json, vite'll think @udecode/plate-juice has side effects and still pack it into the final product, even i dont use @udecode/plate-juice

[zbeyens]

Thanks for reporting this. PR's welcome!