This requires a fair amount of explicit calls to createNameType in StdNames, which is not pleasing to the eye, but the result is a saner codebase nevertheless.

We use the opportunity to replace the n"foo" interopolator trick, which was used to avoid spurious "possible missing interpolator" warnings, by a simple concatenation like "$" + "foo".

In the scala-reflect API, we do not remove the methods to preserve binary compatibility. We simply drop their implicit marker, which is not source compatible but is binary compatible.

After that, we integrate methods of NameOps directly in Name.

Now that there are no more implicit conversion from String to Names, we can safely put those methods directly in Name, which is better for performance and readability. Previously, doing so would cause ambiguous implicit conversions between those and Predef.augmentString.

/cc @diesalbla @hrhino
Inspired by #8535.