feat(grammar): Finalize grammar (#58)

Fix #17

Author: bugwelle

CHANGELOG.md

@@ -17,6 +17,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Updated to tree-sitter v0.22.6
 - grammar:
   + Only structured events (+ projections) are allowed, not scalar ones.
+  + The grammar was updated and finalized.
 
 ### Fixed
 

docs/cds-compiler-differences.md

@@ -9,11 +9,11 @@ artifact definitions.  The syntax highlighter should still work with such code.
 Furthermore, the official `@sap/cds-compiler` project allows more constructs
 than tree-sitter-cds.  That's because `@sap/cds-compiler` has put a lot of work
 into allowing keywords as identifiers at places that tree-sitter-cds does not
-allow or possibly can't allow.  
+allow or possibly can't allow.
 
 That is, tree-sitter-cds does not allow to use certain keywords as identifiers,
 for example, `many` and `array` can't be used as unquoted identifiers, only as
-quoted ones such as `![many]`.
+delimited identifiers such as `![many]`.
 
 We also restrict some constructs to make the tree-sitter grammar easier to read
 and to avoid custom lexer coding.  Differences include, but are not limited to: