custom EnvironmentKey lookup causes compiler error

I receive the following compiler error:

Cannot infer key path from context; consider explicitly specifying a root type

when I attempt an @Environment(\.foodRepository) lookup in a descendant View.

Here's the setup in my App class:

import SwiftUI
import SwiftData

@main
struct BulkCutApp: App {
    
    private var foodRepository: FoodRepository = /* some code*/
    
    var body: some Scene {
        WindowGroup {
            ContentView()
                .foodRepository(foodRepository)
        }
    }
        
}

extension View {
    func foodRepository(_ customValue: FoodRepository) -> some View {
        environment(\.foodRepository, customValue)
    }
}

extension EnvironmentValues {
    var foodRepository: FoodRepository {
        get { self[FoodRepositoryKey.self] }
        set { self[FoodRepositoryKey.self] = newValue }
    }
}
            
struct FoodRepositoryKey: EnvironmentKey {
    static var defaultValue: FoodRepository = FoodRepository(food:[])
}

Nothing special in FoodRepository:

@Observable
class FoodRepository {    
            
    var food: [Food]
    // more code
}