Add diagnostic output to parse_html_for_errors_v2.py

Print count of index.html files found (or fail fast with clear error
if the HTML root directory doesn't exist) so we can confirm the walk
is finding the right path in CI.

Author: iamzoltan

parse_html_for_errors_v2.py

@@ -36,6 +36,19 @@ def main():
     total_removed = 0
     files_touched = 0
 
+    if not os.path.isdir(HTML_ROOT):
+        print(
+            f"ERROR: HTML output directory not found: {HTML_ROOT!r} (cwd={os.getcwd()!r})"
+        )
+        sys.exit(1)
+
+    all_index_files = []
+    for dirpath, _dirnames, filenames in os.walk(HTML_ROOT):
+        for fname in filenames:
+            if fname == "index.html":
+                all_index_files.append(os.path.join(dirpath, fname))
+    print(f"Found {len(all_index_files)} index.html files under {HTML_ROOT}")
+
     for dirpath, _dirnames, filenames in os.walk(HTML_ROOT):
         for fname in filenames:
             if fname != "index.html":