KeychainStore 1.0.0

• Initial release: KeychainStore (data, strings, Codable values, typed keys), one item per key
  across iCloud Keychain sync states, access control with typed errors, async reads for
  prompts, change notifications across processes, KeychainItem and @KeychainStorage for
  SwiftUI, CredentialStore for server logins, migration between services, access groups and
  sync modes, SecureEnclaveKeys, and InMemoryKeychain for tests.