* Add benchmarks for potentially optimizable RuneExtensions
* Add new RuneExtensions.DecodeSurrogatePair benchmark implementation
Avoids intermediate heap array allocations which is especially nice when the rune is not surrogate pair because then array heap allocations are completely avoided.
* Enable nullable reference types in RuneExtensions
* Make RuneExtensions.MaxUnicodeCodePoint readonly
Makes sure no one can accidentally change the value. Ideally would be const value.
* Optimize RuneExtensions.DecodeSurrogatePair
* Remove duplicate Rune.GetUnicodeCategory call
* Add new RuneExtensions.IsSurrogatePair benchmark implementation
Avoids intermediate heap allocations by using stack allocated buffer.
* Optimize RuneExtensions.IsSurrogatePair
* Add RuneExtensions.GetEncodingLength tests
* Optimize RuneExtensions.GetEncodingLength
* Optimize RuneExtensions.Encode
* Print encoding name in benchmark results
* Rename variable to better match return description
* Add RuneExtensions.EncodeSurrogatePair benchmark
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Co-authored-by: Tig <tig@users.noreply.github.com>
