Max_volume for terrain and furniture can be defined with strings

[Fris0uman]

Summary

SUMMARY: Infrastructure "Max_volume for terrain and furniture can be defined with strings"

Purpose of change

Max_volume for terrain and furniture can be defined with strings

Describe the solution

Replace optional() with assign()

Describe alternatives you've considered

Testing

Change bookcase max_volume to "10 L"
load game
No error
Bookcase can hold 10 L

Additional context

Didn't update the doc because it was already saying that using string works.

[I-am-Erk]

Could you explain the concept in the pr please?

[anothersimulacrum]

Instead of max_volume being an integer in units of metric cups, it can be a string where you specify the units.
e.g. "250 L", "20 ml"

[I-am-Erk]

That comment was for a totally different pr, I have no idea how it wound up here