Add native Windows compatibility layer

scripts/claim_ownerless.py

@@ -29,7 +29,7 @@ def main():
         if not os.path.exists(path):
             print(f"  {label}: not found, skipping")
             continue
-        with open(path, "r") as f:
+        with open(path, "r", encoding="utf-8") as f:
             entries = json.load(f)
         count = 0
         for e in entries:
@@ -37,7 +37,7 @@ def main():
                 e["owner"] = owner
                 count += 1
         if count:
-            with open(path, "w") as f:
+            with open(path, "w", encoding="utf-8") as f:
                 json.dump(entries, f, ensure_ascii=False, indent=2)
         print(f"  {label}: claimed {count} entries")