Bug Report

Description of the problem

There's memory leaks when using custom fonts with huge data. I can disable fontLayoutCache but the performance is 3x slower.

I think we should use lru instead of simple object here

Code sample

//TODO:

Your environment

• pdfkit version: 0.15.0
• Node version: 20.14.0
• Browser version (if applicable): -
• Operating System: Mac and Linux