Android Secure Storage #153

#if os(Android)
struct AndroidStorage: Storage {
   ...
}
#endif

class Keychain: @unchecked Sendable {
    /// Initializes the keychain with an overridden accound identifier.
    /// - Parameter account: a key indicating the account owner. Ideally, use the application identifier for this value.
    public init(_ account: String) {
        assert(account.isNotEmpty, "❌ The account identifier cannot be empty.")
        #if canImport(Security)
        self.storage = DefaultStorage(account: account)
        #elseif os(Android)
        self.storage = AndroidStorage(account: account)
        #elseif os(Linux)
        self.storage = LinuxStorage(account: account)
        #endif
    }
}