Add full-width closing bracket support after asciiend

Allow ］ (U+FF3D) after asciiend in ASCII content scanner.
This enables ASCII strings inside arrays with full-width brackets:
  var x = ［ascii...asciiend］

The parser now correctly recognizes this as an array containing
an ASCII string, not as a syntax error.

Fixes 1 additional parsing error.

src/scanner.c

@@ -138,7 +138,7 @@ bool tree_sitter_stonescript_external_scanner_scan(void *payload, TSLexer *lexer
           if (match && (lexer->lookahead == '\n' || lexer->lookahead == '\r' || 
                        lexer->lookahead == ' ' || lexer->lookahead == '\t' || 
                        lexer->lookahead == ',' || lexer->lookahead == ')' ||
-                       lexer->lookahead == ']' ||
+                       lexer->lookahead == ']' || lexer->lookahead == 0xFF3D ||  // ］ full-width
                        lexer->eof(lexer))) {
             lexer->result_symbol = ASCII_CONTENT;
             return has_content;