import CoreModel /// 获取/提交打卡数据的用例。 public struct CheckinUseCase: Sendable { private let repository: CheckinRepository public init(repository: CheckinRepository) { self.repository = repository } public func observeCheckin() -> AsyncThrowingStream { repository.observeCheckin() } public func submitCheckin(status: CheckinStatus) async throws { try await repository.submitCheckin(status: status) } }