Track reopened supply chests and fix API snapshots

mosfet.py

@@ -94,6 +94,24 @@ def _api_plain(value, depth=0):
     return str(value)
 
 
+def _api_json_safe(value, depth=0):
+    """Normalize snapshots for JSON, including non-string dictionary keys."""
+    if depth > 12:
+        return '[nested data omitted]'
+    if value is None or isinstance(value, (str, int, float, bool)):
+        return value
+    if isinstance(value, dict):
+        return {str(key): _api_json_safe(item, depth + 1)
+                for key, item in value.items()}
+    if isinstance(value, (list, tuple, set)):
+        return [_api_json_safe(item, depth + 1) for item in value]
+
+    converted = _api_json_default(value)
+    if converted is value:
+        return str(value)
+    return _api_json_safe(converted, depth + 1)
+
+
 def _api_json_default(value):
     """Serialize live protocol objects without invoking fragile __repr__ code."""
     from minecraft.networking.packets import Packet
@@ -133,7 +151,7 @@ def api_global():
             'dimension': chunks.dimension,
         }
     response = app.response_class(
-        response=json.dumps(snapshot, default=_api_json_default),
+        response=json.dumps(_api_json_safe(snapshot)),
         status=200,
         mimetype='application/json'
     )