Give another go at ZString

[Marvin-Brouwer]

Is your feature request related to a problem? Please describe.
Performance improvements are always nice.
Apparently ZString is fast and allocates similar to cashed StringBuilder:
https://twitter.com/KStrubeG/status/1593529443024109570

Describe the solution you'd like
Give a go at ZString and see how it affects the benchmarks.

Describe alternatives you've considered
-

Additional context
We have an interface ITextWriter.cs you should just be able to create an implementation for that.
However, you may need to completely remove the StringBuilderPool from the equation.

We've tried this at the start of this project and couldn't get this to work.
Because of that, we tried to copy code from an old library and combine it with ZString code and it didn't end being faster or more memory efficient.
However, that may as well have been our fault.

[Marvin-Brouwer]

If it does end up being more performant, perhaps it's a good idea to create a factory so we can use ZString for UTF-8 and UTF-16 and then for everything else fall back to the existing implementation.