Preview what deleting items at these paths would reach

Answers what a delete would remove beyond the rows named, without deleting anything. Takes the same body the delete takes and resolves it through the same cascade, so the preview cannot disagree with the outcome. Only SECONDARY references come back — the reviewer, submission and public-release copies that would go with the selection — not the rows the caller listed. Costs the same right as the delete itself (`canDeleteCreatorItems` / `canDeleteReviewerItems`). A cheaper preview would hand out the labels of submissions and public releases the caller cannot otherwise see.

curl -X POST "https://example.com/projects/497f6eca-6276-4993-bfeb-53cbbbba6f08/files/creator/delete-preview" \  -H "Content-Type: application/json" \  -d '{    "itemPaths": [      "Renders/old.png"    ]  }'

{  "selectedCount": 0,  "affectedAssetCount": 0,  "counts": {    "reviewer": 0,    "submission": 0,    "public": 0,    "other": 0  },  "references": [    {      "fileSystemId": "b1428d76-db1d-49f6-99a8-028a6fc81c52",      "assetId": "9179b887-04ef-4ce5-ab3a-b5bbd39ea3c8",      "assetName": "string",      "kind": "reviewer",      "path": "string",      "itemPath": "string",      "label": "string"    }  ]}