This code seems like it should compile, conceptually, but it doesn't. Compiler says JobApplication doesn't conform to Hashable.

Handling GraphQL Types with Protocols

struct JobApplication: Hashable, Identifiable {
    var id: String
    var jobPostingId: String
    var answers: [CustomQuestionAnswer]
    var questions: [CustomQuestion]
}

protocol CustomQuestion: Hashable, Identifiable {
    var id: String { get set }
    var prompt: String { get set }
    var required: Bool { get set }
}

struct BoolQuestion: CustomQuestion {
    var id: String
    var prompt: String
    var required: Bool
}

struct TextQuestion: CustomQuestion {
    var id: String
    var prompt: String
    var required: Bool
    var length: Int
}

struct NumericQuestion: CustomQuestion {
    var id: String
    var prompt: String
    var required: Bool
    var minimum: Int
    var maximum: Int
}

protocol CustomQuestionAnswer: Hashable, Identifiable {
    var id: String { get set }
}

struct BoolCustomQuestionAnswer: CustomQuestionAnswer {
    var id: String
    var question: BoolQuestion
    var value: Bool
}

struct TextCustomQuestionAnswer: CustomQuestionAnswer {
    var id: String
    var question: TextQuestion
    var value: String
}

struct NumericCustomQuestionAnswer: CustomQuestionAnswer {
    var id: String
    var question: NumericQuestion
    var value: Int
}