pl752

Upd5: TLDR: Implemented set of synthetic benchmarks to test the main changes themselves (isolated from IO) along with some alternative implementations of read/write methods. Huge improvements in rune processing methods....

Upd6: I have decided to experiment with inplace buffering with MemoryMarshal.AsBytes and .CreateSpan, but the changes aren't very relevant (aside from potential stack memory consumption reduction), as the overall performance...

Also I am still waiting for reviews/opinions, I can make any adjustments required, or separate out most yielding changes (like rune processing), if the small optimizations are too complicated to...

Upd8: Decided to implement some size edge cases and ~ascii-only~ bmp-only strings specific optimizations to rune related methods, also replaced some unneeded methods. Rune impl benchmarks ``` | Method |...

Decided to close the PR and split it up due to changes being too broad. New PRs (#1252 and #1253) were created instead, these contain mostly the same significant changes,...