fix(move): recalculate sub_type when moving models across roots

Moving a checkpoint into a unet root (or vice versa) moved the file and
updated the in-memory cache, but three stale spots survived until a
manual cache rebuild:

- The moved .metadata.json kept the old sub_type, and the opportunistic
  sync_cache_from_metadata path (fired by get_model_metadata and example
  image metadata updates) trusted it, reverting the cache entry and the
  SQLite snapshot to the pre-move sub_type. Loader nodes filter strictly
  on sub_type, so the model stayed listed under the old type.
- The manager page discarded the move response's cache_entry, so the
  card badge (CKPT/DM) and context menu label kept showing the old type.

Fixes:
- move_model now re-resolves sub_type from the target location (new
  resolve_sub_type_for_path hook) and persists it into the moved
  .metadata.json.
- _sync_cache_from_metadata_impl runs desired entries through
  adjust_cached_entry so location-derived fields cannot be re-poisoned
  by stale metadata snapshots.
- MoveManager carries cache_entry.sub_type into the in-place card
  update so badge and context menu reflect the new type immediately.

py/services/checkpoint_scanner.py

@@ -410,6 +410,10 @@ class CheckpointScanner(ModelScanner):
 
         return None
 
+    def resolve_sub_type_for_path(self, file_path: Optional[str]) -> Optional[str]:
+        """Resolve sub_type from the configured root that contains the file."""
+        return self._resolve_sub_type(self._find_root_for_file(file_path))
+
     def adjust_metadata(self, metadata, file_path, root_path):
         """Adjust metadata during scanning to set sub_type."""
         sub_type = self._resolve_sub_type(root_path)
@@ -419,9 +423,7 @@ class CheckpointScanner(ModelScanner):
 
     def adjust_cached_entry(self, entry: Dict[str, Any]) -> Dict[str, Any]:
         """Adjust entries loaded from the persisted cache to ensure sub_type is set."""
-        sub_type = self._resolve_sub_type(
-            self._find_root_for_file(entry.get("file_path"))
-        )
+        sub_type = self.resolve_sub_type_for_path(entry.get("file_path"))
         if sub_type:
             entry["sub_type"] = sub_type
         return entry