probe and routing partial-file guards check the partial key alone, not status #700

The same cause as the atoms reader fixed for the atoms file: a result file marked only by "status": "partial" is read as finished.

• dokimi/dokimi/novelty/items.py:271 (_refuse_partial, used by novelty items): _refuse_partial("p.json", {"status": "partial"}) returns None, where a {"partial": {...}} file raises ProbeFileError.
• dokimi/dokimi/commands/novelty_routing_report.py:520 (_is_partial_file): returns False for a file holding {"status": "partial"}, so a finished-file overwrite guard treats it as a finished result.

Fix: test "partial" in data or data.get("status") == "partial" at both sites (items.py is also changed by the open #633 and load_artifact in artifacts.py is covered there, so land it after or with that PR), with a test per site.

Found while fixing #642. The fix's PR is #702.