Fixed inspector precision issues when editing floats

Created by: aqnuep

For some reason the editor limits the precision of all floating-point values, including vectors, matrices, etc. to 3 decimal places after the decimal point (as they all have a step of 0.001).

This change gets rid of this artificial limitation at least for the basic types and uniforms.

The implementation of step_decimals() is also changed to use log10 instead of a loop, and it will now correctly handle a step size of zero and return maxn while previously it incorrectly returned 0 in this case.

Fixes #18251 (at least).