fixed dot operator recursive loop & macro suggest (#16922)

* basic stability improvements; refs nimsuggest
* fixed dot operator recursive loop & macro suggest
* hacky fix for run away dot operator sem check

Committing this mostly to make the issue more clear. Perhaps get better
feedback.

* semExprWithType seems like a better place to check
* fixed error messages const case expressions
* Clean-up test
* stopped the dot operator madness

No longer get infinite recursion when seming broken code with a dot
operator macro like in jsffi.

Co-authored-by: Araq <rumpf_a@web.de>

nimsuggest/tests/twithin_macro.nim

@@ -41,15 +41,11 @@ echo r.age_human_yrs()
 echo r
 
 discard """
-disabled:true
-$nimsuggest --tester $file
+$nimsuggest --tester --maxresults:5 $file
 >sug $1
 sug;;skField;;age;;int;;$file;;6;;6;;"";;100;;None
 sug;;skField;;name;;string;;$file;;5;;6;;"";;100;;None
 sug;;skMethod;;twithin_macro.age_human_yrs;;proc (self: Animal): int;;$file;;8;;9;;"";;100;;None
 sug;;skMethod;;twithin_macro.vocalize;;proc (self: Animal): string;;$file;;7;;9;;"";;100;;None
 sug;;skMethod;;twithin_macro.vocalize;;proc (self: Rabbit): string;;$file;;23;;9;;"";;100;;None
-sug;;skMacro;;twithin_macro.class;;proc (head: untyped, body: untyped): untyped{.gcsafe, locks: <unknown>.};;$file;;4;;6;;"";;50;;None*
 """
-
-# TODO: disabled due to semantic error reporting in nimsuggest results

nimsuggest/tests/twithin_macro_prefix.nim

@@ -46,10 +46,3 @@ $nimsuggest --tester $file
 sug;;skField;;age;;int;;$file;;6;;6;;"";;100;;Prefix
 sug;;skMethod;;twithin_macro_prefix.age_human_yrs;;proc (self: Animal): int;;$file;;8;;9;;"";;100;;Prefix
 """
-
-#[
-TODO: additional calls to `>sug $1` produces different output with errors,
-      possibly related to cached results from the first analysis, which refers
-      to expanded macros/templates which rely on imported symbols from `system`
-      module that are not present in this module.
-]#