[Bug] enum cases are not encoded unless type specified

[Amzd]

• I have read the documentation.
• I have read the limitations.
• I could not find my issue.

Describe the bug

Encoding of enums is missing

@Codable
enum Foo {
    case test
}
// generates:
extension Foo: Decodable {
    init(from decoder: any Decoder) throws {
        let container = try decoder.container(keyedBy: DecodingKeys.self)
        guard container.allKeys.count == 1 else {
            let context = DecodingError.Context(
                codingPath: container.codingPath,
                debugDescription: "Invalid number of keys found, expected one."
            )
            throw DecodingError.typeMismatch(Self.self, context)
        }
        let contentDecoder = try container.superDecoder(forKey: container.allKeys.first.unsafelyUnwrapped)
        switch container.allKeys.first.unsafelyUnwrapped {
        case DecodingKeys.test:
            self = .test
        }
    }
}

extension Foo: Encodable {
    func encode(to encoder: any Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        switch self {
        case .test:
            break
        }
    }
}

extension Foo {
    enum CodingKeys: String, CodingKey {
        case test = "test"
    }
    enum DecodingKeys: String, CodingKey {
        case test = "test"
    }
}

which means Foo.test just encodes to "{}" which is not useful and asymmetric to how it decodes