[Feature] - LazyEncodedString and UTF8 literals everywhere

[smaillet]

Is your feature request related to a problem? Please describe.
Currently it is not plausible to use UTF8 literals unless an API already supports LazyEncodedString. (Or directly accepts ReadOnlySpan<byte>). Thus, there is a conversion cost to get into the UTF8 form needed by the native LLVM-C API.

Describe the solution you'd like
Convert all of the wrapper classes to accept LazyEncodedString and adjust interop import signatures to allow pre-encoded strings. (No need for marshalling attributes). This includes updates to DisposeMessageMarshaller so that it produces a LazyEncodedString

Describe alternatives you've considered
Keep on plugging away with what is there, it works but, often has overhead that is simply wasting cycles.

Additional context
This hasn't been a focus yet as it's a matter of performance, not correctness.

[smaillet]

This is now mostly done, though no formal verification of use was performed.