fix(codegen): ensure multiple line comments are grouped.

Author: sruehl

code-generation/protocol-base-mspec/src/main/antlr4/org/apache/plc4x/plugins/codegenerator/language/mspec/MSpec.g4

@@ -415,13 +415,21 @@ STRING_CHARACTER
  ;
 
 LINE_COMMENT
- : ('//' ~[\r\n]*)+ -> channel(HIDDEN)
+ : (('//' ~[\r\n]*)+) -> channel(HIDDEN)
  ;
 
 BLOCK_COMMENT
  : '/*' .*? '*/' -> channel(HIDDEN)
  ;
 
+EmptyLine
+ : {getCharPositionInLine() == 0}? [ \t]* '\r'? '\n' -> channel(HIDDEN)
+ ;
+
+NEWLINE
+ : '\r'? '\n' -> channel(HIDDEN)
+ ;
+
 WS
- : [ \t\r\n\u000C]+ -> channel(HIDDEN)
+ : [ \t\u000C]+ -> channel(HIDDEN)
  ;

code-generation/protocol-base-mspec/src/main/java/org/apache/plc4x/plugins/codegenerator/language/mspec/parser/MessageFormatListener.java

@@ -103,7 +103,7 @@ private String consumePendingComment(ParserRuleContext ctx) {
         List<Token> hiddenToLeft = tokenStream.getHiddenTokensToLeft(tokenIndex);
         if (hiddenToLeft != null) {
             hiddenToLeft.reversed().stream()
-                .takeWhile(token -> frontComments.isEmpty() || (token.getType() != MSpecLexer.WS))
+                .takeWhile(token -> frontComments.isEmpty() || (token.getType() != MSpecLexer.EmptyLine))
                 .filter(token -> token.getType() == MSpecLexer.LINE_COMMENT || token.getType() == MSpecLexer.BLOCK_COMMENT)
                 .forEach(frontComments::add);
         }