text measure function

[ickshonpe]

Objective

Fixes #19382

Solution

Function measure_text creates a temporary cosmic buffer to shape the text and return the size of the laid out text.
This isn't very good but should work.

Testing

[viridia]

This looks great. We can always improve it later.

[viridia]

Release note suggestion:

Game worlds often have in-game text for signboards and placards. The measure_text function can be used to determine the width and height of a text string (using a specified font) so that the words can be appropriate scaled to fit the available space.