missing semicolon (";") detection improvement

Hello.

**Feature request description**
I help some new RPG developers using VSCode/Code for i. And the most encoureted error is a missing semicolon (" ; ") at the end of an instruction, especially at the declaration level (dcl-s and dcl-ds).

And sometimes, I don't see it quickly and spend a lot of time to seek something else.

**RDi comparison**
In VSCode, when I remove an ending semicolon in a DS declaration (or after a calculation intruction), it appears this way:
As you can see, there is no warning to indicate that the second DS cannot be resolved because of the missing semicolon.

In RDi, the same member appears this way:
As you can see, on the line following the one where the semicolon is missing, there is a red cross to indicate the parsing issue.

**Describe the solution you'd like**
It would be great to indicate on the following line that the semicolon is missing, with a message or underlines like other errors.

**Describe alternatives you've considered**
I didnt't found anywhere to set on something to help to set focus on an error like missing semicolon. Perhaps I missed something.

Thanks for your great job around Code for i!