feat: add error information in the progress callback

This allows users to bail parsing if an error was *definitely* detected
using the progress callback, as all possible stack versions have a
non-zero error cost.

Co-authored-by: Amaan Qureshi <amaanq12@gmail.com>

lib/binding_web/src/parser.ts

@@ -53,6 +53,9 @@ export interface ParseOptions {
 export interface ParseState {
   /** The byte offset in the document that the parser is at. */
   currentOffset: number;
+
+  /** Indicates whether the parser has encountered an error during parsing. */
+  hasError: boolean;
 }
 
 /**