I am attempting to load this JSON data into a SwiftData Model:

{
    "1": {
        "id": "1",
        "breed": "Bulldog Francés",
        "fur": "Corto",
        "furColor": "Gris",
        "gender": "Hembra",
        "imageUrl": "https://http2.mlstatic.com/D_NQ_NP_714611-MEC50253081381_062022-O.jpg",
        "lifeExpectancy": 10
    },
    "2": {
        "id": "2",
        "breed": "french poodle",
        "fur": "Corto",
        "furColor": "Blanco",
        "gender": "Macho",
        "imageUrl": "https://http2.mlstatic.com/D_NQ_NP_693633-MEC50152204932_052022-O.jpg",
        "lifeExpectancy": 16
    },
}

I have Created a model for the Data:

import Foundation
import SwiftData



//model for an animal card
@Model
class Dog: Codable, Identifiable {
    
    
    enum CodingKeys: CodingKey  {
        case id
        case breed
        case fur
        case furColor
        case gender
        case imageUrl
        case lifeExpectancy
    }
    
    
    var id: String
    var breed: String
    var fur: String
    var furColor: String
    var gender: String
    var imageUrl: String
    var lifeExpectancy: Int
    
    init(id: String,breed: String, fur: String, furColor: String, gender: String, imageUrl: String, lifeExpectancy: Int) {
        self.id = id
        self.breed = breed
        self.fur = fur
        self.furColor = furColor
        self.gender = gender
        self.imageUrl = imageUrl
        self.lifeExpectancy = lifeExpectancy
    }
    
    required init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        id = try container.decode(String.self, forKey: .id)
        breed = try container.decode(String.self, forKey: .breed)   
        fur = try container.decode(String.self, forKey: .fur)
        furColor = try container.decode(String.self, forKey: .furColor)
        gender = try container.decode(String.self, forKey: .gender)
        imageUrl = try container.decode(String.self, forKey: .imageUrl)
        lifeExpectancy = try container.decode(Int.self, forKey: .lifeExpectancy)
    }
    
    func encode(to encoder: any Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(id, forKey: .id)
        try container.encode(breed, forKey: .breed)
        try container.encode(fur, forKey: .fur)
        try container.encode(furColor, forKey: .furColor)
        try container.encode(gender, forKey: .gender)
        try container.encode(imageUrl, forKey: .imageUrl)
        try container.encode(lifeExpectancy, forKey: .lifeExpectancy)
    }

}

And then I am attempting to load it In but I am getting Failed to pre-seed database printed, I have confirmed the Url is correct so I am unsure what could be the problem:

@main
struct AnimalGuesserApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
        .modelContainer(for: Dog.self) { result in
            do {
                   let container = try result.get()

                   // Check we haven't already added our users.
                   let descriptor = FetchDescriptor<Dog>()
                   let existingDogs = try container.mainContext.fetchCount(descriptor)
                   guard existingDogs == 0 else { return }
                    
                   // Load and decode the JSON.
                   guard let url = Bundle.main.url(forResource: "dogs", withExtension: "json") else {
                       fatalError("Failed to find dogs.json")
                   }
                
                    print("URL:", url)
                
                   let data = try Data(contentsOf: url)
                   let dogs = try JSONDecoder().decode([Dog].self, from: data)
                
                print(dogs)
          

                   // Add all our data to the context.
                   for dog in dogs {
                       print(dog.breed)
                       container.mainContext.insert(dog)
                   }
               } catch {
                   print("Failed to pre-seed database.")
               }
        }
    }
}

I am sure the json is added to the target and the name is correct but loading the contents of the url just seems to throw an exception.