e4e55ea01a
The pin loader was storing port items verbatim in the on-wire shape
[{json: ..., binary: null}]. The executor's WrapPin treats each pin-array
element as one item's whole payload, so the wrapper leaked in: scripts saw
items[0] == {"json": ..., "binary": null} and items[0]["test"] raised
KeyError instead of returning the value.
Now the loader unwraps each item to its .json payload before storing.
Updated the existing test assertion and added a multi-item regression.