fix(javascript-calculator): removing +0 and -0 from the expression displayed on calculator.

[CallmeHongmaybe]

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Partially closes #49045

With the 6 trailing zeros gone, I think it's still useful to remove any arithmetic involving zeros. That way the expression looks cleaner and the fix can even handle cases where the user types --0.

[CallmeHongmaybe]

Hey maintainers, Before we can merge, how can I tag in @spiritanand as my fellow contributor?

[CallmeHongmaybe]

@scissorsneedfoodtoo thanks for the edge case.