Responses with assets could be nicer

[rahimklaber]

Maybe something like this:

@Serializable
@SerialName("change_trust")
data class ChangeTrustResponse(
    override val id: String, //long?
    @SerialName("asset_type") val assetType: String,
    @SerialName("asset_code") val assetCode: String? = null,
    @SerialName("asset_issuer") val assetIssuer: String? = null,
    @SerialName("_links") override val links : Links,
    val limit: String,
    val trustee: String? = null,
    val trustor: String,
    val sponsor: String? = null,
    @SerialName("liquidity_pool_id") val liquidityPoolId: String? = null,
) : OperationResponse{
val asset by lazy{
        Asset.Native()
    }


}