Add images to inventory items

[git-wil]

Goal

When searching for items in inventory, it could be nice to show a preview image of what the actual item looks like, so users can know exactly what the item is in real life. It would be a massive undertaking to add images to every item, which would likely need to happen over a summer.

Subtasks

• Modify the InventoryItem schema to include an image link
• Implement a way to add images to items in the inventory editor
• Implement a way for users to see the image preview in the inventory search (likely in the More Info tab)
• Update inventory items with images