Allow ) and ] after asciiend in ASCII blocks

ASCII blocks can now be used as function arguments and array
elements. The scanner now accepts ) and ] as valid characters
after 'asciiend', allowing constructs like:
- var x = uiAA(ascii...asciiend)
- var y = [ascii...asciiend]

Fixes 12 parsing errors in test scripts.

src/scanner.c

@@ -134,10 +134,11 @@ bool tree_sitter_stonescript_external_scanner_scan(void *payload, TSLexer *lexer
             }
           }
           
-          // Check that asciiend is followed by whitespace or EOL
+          // Check that asciiend is followed by whitespace or EOL or closing delimiters
           if (match && (lexer->lookahead == '\n' || lexer->lookahead == '\r' || 
                        lexer->lookahead == ' ' || lexer->lookahead == '\t' || 
-                       lexer->lookahead == ',' || 
+                       lexer->lookahead == ',' || lexer->lookahead == ')' ||
+                       lexer->lookahead == ']' ||
                        lexer->eof(lexer))) {
             lexer->result_symbol = ASCII_CONTENT;
             return has_content;