Major Description
Currently the `histogram_numeric` function always returns a struct of (x, y) double-precision floating-point pairs. However, the function may accept various numeric input types including integers, intervals, etc., in which case users must generally explicitly cast the double-precision result back to the original input type. In this improvement, we will update the output type to propagate the input type to the output.
Note that usage analysis for this function does not appear to yield much traffic currently, so it seems OK to just change the output type directly.
