Deck Editor and newly added images.

Since recent updates, in most cases newly added images get loaded fairly easily.

In draft, new images will be displayed when:
* receiving a new pack
* selecting a card and thus moving it from pack to pool
* restoring cards from sideboard

On battlefield, new images are loaded whenever a card changes zones.

However, in the deck editior, new images don't seem to load.
I've tried:
* moving cards between maindeck and sideboard, and
* reloading the deck from a file.

When I move a card, the image shows whilst it is in transit, but is back to no image once it lands in its new location.

Start in the deck editor's image-loading path and reproduce the issue by moving cards between the maindeck and sideboard, then reloading the deck from a file. Compare the behavior with draft and battlefield image updates; done means newly added images remain visible after cards land in their new deck locations.

Written by the indexing model from the issue text.