curl --request GET \
  --url https://api.shelv.dev/v1/shelves/{id}/diff \
  --header 'Authorization: Bearer <token>'

{
  "files": [
    {
      "patch": "<string>",
      "path": "<string>",
      "truncated": true
    }
  ],
  "from": 123,
  "shelfPublicId": "<string>",
  "summary": {
    "added": 1,
    "modified": 1,
    "removed": 1,
    "totalFiles": 1,
    "unchanged": 1
  },
  "to": 123
}