从 iOS 17 Observation 迁移至 iOS 16 兼容的 Combine 架构

将最低部署版本降至 iOS 16，以 ObservableObject 替换 @Observable，新增导航与 UI 兼容层，并补充登录冒烟 UI 测试。

Co-authored-by: Cursor <cursoragent@cursor.com>

suixinkan/App/State/AccountContext.swift

@@ -5,7 +5,7 @@
 //  Created by Codex on 2026/6/18.
 //
 
-import Observation
+import Combine
 
 /// 当前账号的基础资料实体，用于跨页面展示昵称、手机号和头像。
 struct AccountProfile: Codable, Equatable {
@@ -58,14 +58,13 @@ struct BusinessScope: Codable, Equatable, Identifiable {
 }
 
 @MainActor
-@Observable
 /// 账号上下文状态中心，保存当前账号资料和景区/门店作用域。
-final class AccountContext {
-    private(set) var profile: AccountProfile?
-    private(set) var scenicScopes: [BusinessScope] = []
-    private(set) var storeScopes: [BusinessScope] = []
-    var currentScenic: BusinessScope?
-    var currentStore: BusinessScope?
+final class AccountContext: ObservableObject {
+    @Published private(set) var profile: AccountProfile?
+    @Published private(set) var scenicScopes: [BusinessScope] = []
+    @Published private(set) var storeScopes: [BusinessScope] = []
+    @Published var currentScenic: BusinessScope?
+    @Published var currentStore: BusinessScope?
 
     /// 应用登录成功后写入账号资料。
     func applyLogin(profile: AccountProfile? = nil) {

suixinkan/App/State/AppSession.swift

@@ -6,7 +6,7 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 /// 登录阶段实体，表示根视图当前应该展示的认证状态。
 enum AuthPhase: Equatable {
@@ -16,11 +16,10 @@ enum AuthPhase: Equatable {
 }
 
 @MainActor
-@Observable
 /// 登录会话状态中心，保存 token 和当前认证阶段。
-final class AppSession {
-    private(set) var phase: AuthPhase = .loggedOut
-    private(set) var token: String?
+final class AppSession: ObservableObject {
+    @Published private(set) var phase: AuthPhase = .loggedOut
+    @Published private(set) var token: String?
 
     var isLoggedIn: Bool {
         phase == .loggedIn

suixinkan/App/State/AuthSessionCoordinator.swift

@@ -6,15 +6,14 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 @MainActor
-@Observable
 /// 登录会话协调器，统一处理登录完成、退出登录和缓存同步。
 final class AuthSessionCoordinator {
-    @ObservationIgnored private let tokenStore: SessionTokenStore
-    @ObservationIgnored private let snapshotStore: AccountSnapshotStore
-    @ObservationIgnored private let preferencesStore: AppPreferencesStore
+    private let tokenStore: SessionTokenStore
+    private let snapshotStore: AccountSnapshotStore
+    private let preferencesStore: AppPreferencesStore
 
     /// 初始化登录会话协调器，并注入 token、账号快照和偏好存储。
     init(

suixinkan/App/State/PermissionContext.swift

@@ -6,15 +6,14 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 @MainActor
-@Observable
 /// 权限上下文状态中心，保存角色权限、当前角色和扁平化权限 URI。
-final class PermissionContext {
-    private(set) var rolePermissions: [RolePermissionResponse] = []
-    private(set) var permissionURIs: Set<String> = []
-    var currentRole: RoleInfo?
+final class PermissionContext: ObservableObject {
+    @Published private(set) var rolePermissions: [RolePermissionResponse] = []
+    @Published private(set) var permissionURIs: Set<String> = []
+    @Published var currentRole: RoleInfo?
 
     /// 替换角色权限列表，并尽量按缓存角色 ID 保持当前角色。
     func replaceRolePermissions(_ rolePermissions: [RolePermissionResponse], currentRoleId: Int? = nil) {

suixinkan/App/State/ScenicSpotContext.swift

@@ -6,7 +6,7 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 /// 景点加载阶段实体，表示当前景区景点列表的加载状态。
 enum ScenicSpotLoadState: Equatable {
@@ -17,12 +17,11 @@ enum ScenicSpotLoadState: Equatable {
 }
 
 @MainActor
-@Observable
 /// 景点上下文状态中心，保存当前景区下的景点或打卡点列表。
-final class ScenicSpotContext {
-    private(set) var scenicId: Int?
-    private(set) var spots: [ScenicSpotItem] = []
-    private(set) var loadState: ScenicSpotLoadState = .idle
+final class ScenicSpotContext: ObservableObject {
+    @Published private(set) var scenicId: Int?
+    @Published private(set) var spots: [ScenicSpotItem] = []
+    @Published private(set) var loadState: ScenicSpotLoadState = .idle
 
     /// 按景区 ID 重新加载景点列表，失败只影响景点模块本身。
     func reload(scenicId: Int?, api: AccountContextServing) async {

suixinkan/App/State/SessionBootstrapper.swift

@@ -6,14 +6,13 @@
 //
 
 import Foundation
-import Observation
+import Combine
 
 @MainActor
-@Observable
 /// 登录态启动恢复器，负责冷启动时从缓存恢复并校验 token。
 final class SessionBootstrapper {
-    @ObservationIgnored private let tokenStore: SessionTokenStore
-    @ObservationIgnored private let snapshotStore: AccountSnapshotStore
+    private let tokenStore: SessionTokenStore
+    private let snapshotStore: AccountSnapshotStore
     private var didAttemptRestore = false
 
     /// 初始化启动恢复器，并注入 token 与账号快照存储。

suixinkan/App/State/ToastCenter.swift

@@ -5,17 +5,16 @@
 //  Created by Codex on 2026/6/18.
 //
 
-import Observation
+import Combine
 import SwiftUI
 
 @MainActor
-@Observable
 /// 全局 Toast 状态中心，负责保存和清除当前提示文案。
-final class ToastCenter {
-    fileprivate var message: String?
-    @ObservationIgnored private let autoDismissNanoseconds: UInt64
-    @ObservationIgnored private var dismissTask: Task<Void, Never>?
-    @ObservationIgnored private var displayToken: UInt64 = 0
+final class ToastCenter: ObservableObject {
+    @Published fileprivate var message: String?
+    private let autoDismissNanoseconds: UInt64
+    @Published private var dismissTask: Task<Void, Never>?
+    @Published private var displayToken: UInt64 = 0
 
     /// 创建 Toast 状态中心，默认 2.2 秒后自动隐藏。
     init(autoDismissNanoseconds: UInt64 = 2_200_000_000) {
@@ -65,7 +64,7 @@ final class ToastCenter {
 
 /// 全局 Toast 叠加层修饰器，负责把 Toast 展示到页面顶部。
 private struct GlobalToastOverlay: ViewModifier {
-    @Environment(ToastCenter.self) private var toastCenter
+    @EnvironmentObject private var toastCenter: ToastCenter
 
     func body(content: Content) -> some View {
         content