suggestion: ability to read C string for FFI

[DjDeveloperr]

Suggestion

A readCString or similar function in maybe Deno.DynamicLibrary that accepts a pointer (as BigInt) and returns the C String.

Why?

When working with FFI, it's pretty common to use C strings. But in case of Deno FFI it's not possible to do that without a helper function. Right now I'm interacting with a native library directly using Deno FFI (without wrapping it) and I have to make such helper function by making another native library.

Why function and not a string return type?

Only being able to read C strings returned from some function is limiting in my case. In the dylib I'm using, some functions write a C String pointer to a char** instead.

[DjDeveloperr]

Implemented by #12828