Consider allowing math functions for numeric input fields

It's very handy to be able to select a number in a numeric input field and typing something like `2 * 2.25 ` and having the number update to `4.5`.
For example, you might have an object placed somewhere along the ground (not on the grid) and want another set of evenly spaced duplicates.
Or an object is rotated on some arbitrary axis and you want it rotated exactly 'half' of it's current rotation. ( ` / 2 `)

Blender and other 3d software have similar options that could be used as reference.

Start by locating the numeric input entry points in Spoke and identify how values are currently parsed and applied to object transforms. Compare the requested examples, such as `2 * 2.25` and `/ 2`, with Blender's behavior; done means supported expressions update numeric fields correctly without breaking ordinary numeric input.

Written by the indexing model from the issue text.