Allow use-defined precision in XYZWriter

[ChiahsinChu]

Is your feature request related to a problem?

I found a loss of precision when writing XYZ files with XYZWriter (which should be 10.5f), which might be a problem if the absolute values of data are small.

Describe the solution you'd like

I would like to make the precision as a user-defined variable, as what XTCWriter have implemented.

Additional context

A possible implementation and the corresponding UT in #4771