fixes#22598, properly fixes#21887 and fixes test case issue number
When an enum field sym choice has to choose a type, check if its name is
ambiguous in the local scope, then check if the first symbol found in
the local scope is the first symbol in the sym choice. If so, choose
that symbol. Otherwise, give an ambiguous identifier error.
The dependence on the local scope implies this will always give
ambiguity errors for unpicked enum symchoices from generics and
templates and macros from other scopes. We can change `not
isAmbiguous(...) and foundSym == first` to `not (isAmbiguous(...) and
foundSym == first)` to make it so they never give ambiguity errors, and
always pick the first symbol in the symchoice. I can do this if this is
preferred, but no code from CI seems affected.
* clean up some test categories
* mention exact slice issue
* magics into system
* move trangechecks into overflow
* move tmemory to system
* try fix CI
* try fix CI
* final CI fix
