feat: 修复MainView Tab切换问题并优化MeView逻辑

- 新增MainView Tab切换问题分析文档，详细描述问题原因及解决方案。
- 优化BottomTabView的绑定逻辑，简化状态管理，确保Tab切换时状态正确更新。
- 在MeView中实现用户信息加载逻辑调整，确保动态列表仅在首次进入时加载，并添加错误处理视图。
- 创建EmptyStateView组件，提供统一的空状态展示和重试功能。
- 增强调试信息输出，便于后续问题排查和用户体验提升。

yana/Features/MainFeature.swift

@@ -26,6 +26,19 @@ struct MainFeature {
             debugInfoSync("🏗️ MainFeature 初始化")
             debugInfoSync("   accountModel.uid: \(accountModel?.uid ?? "nil")")
             debugInfoSync("   转换后的uid: \(uid)")
+            
+            // 如果没有传入accountModel，尝试从Keychain获取
+            if accountModel == nil {
+                debugInfoSync("   🔍 尝试从Keychain获取AccountModel")
+                Task {
+                    if let savedAccountModel = await UserInfoManager.getAccountModel() {
+                        debugInfoSync("   ✅ 从Keychain获取到AccountModel: \(savedAccountModel.uid ?? "nil")")
+                    } else {
+                        debugInfoSync("   ⚠️ 从Keychain未获取到AccountModel")
+                    }
+                }
+            }
+            
             var meState = MeFeature.State(displayUID: uid > 0 ? uid : nil)
             if uid > 0 {
                 meState.uid = uid // 确保uid与displayUID一致
@@ -73,15 +86,34 @@ struct MainFeature {
                     await send(.accountModelLoaded(accountModel))
                 }
             case .selectTab(let tab):
+                debugInfoSync("🎯 MainFeature selectTab: \(tab)")
+                debugInfoSync("   当前selectedTab: \(state.selectedTab)")
+                debugInfoSync("   新selectedTab: \(tab)")
+                
+                // 避免重复设置相同的tab
+                guard state.selectedTab != tab else {
+                    debugInfoSync("   ⚠️ 重复设置相同tab，忽略")
+                    return .none
+                }
+                
                 state.selectedTab = tab
                 state.navigationPath = []
-                if tab == .other, let uidStr = state.accountModel?.uid, let uid = Int(uidStr), uid > 0 {
-                    if state.me.displayUID != uid {
-                        state.me.displayUID = uid
-                        state.me.uid = uid // 同步更新uid
-                        state.me.isFirstLoad = true
+                debugInfoSync("   ✅ selectedTab已更新为: \(state.selectedTab)")
+                
+                // 切换到MeView时，确保有有效的uid并触发数据加载
+                if tab == .other {
+                    if let uidStr = state.accountModel?.uid, let uid = Int(uidStr), uid > 0 {
+                        if state.me.displayUID != uid {
+                            state.me.displayUID = uid
+                            state.me.uid = uid // 同步更新uid
+                            state.me.isFirstLoad = true
+                            debugInfoSync("   🔄 更新MeFeature状态，uid: \(uid)")
+                        }
+                        debugInfoSync("   📱 切换到MeView，触发数据加载")
+                        return .send(.me(.onAppear))
+                    } else {
+                        debugInfoSync("   ⚠️ 切换到MeView但uid无效，等待AccountModel加载")
                     }
-                    return .send(.me(.onAppear))
                 }
                 return .none
             case .feedList(.testButtonTapped):
@@ -97,14 +129,31 @@ struct MainFeature {
                 return .none
             case let .accountModelLoaded(accountModel):
                 state.accountModel = accountModel
-                // 如果当前选中的是 MeView 标签页，且有有效的 uid，则触发数据加载
-                if state.selectedTab == .other, let uidStr = accountModel?.uid, let uid = Int(uidStr), uid > 0 {
+                debugInfoSync("📦 MainFeature: AccountModel已加载")
+                debugInfoSync("   uid: \(accountModel?.uid ?? "nil")")
+                
+                // 更新MeFeature状态
+                if let uidStr = accountModel?.uid, let uid = Int(uidStr), uid > 0 {
                     if state.me.displayUID != uid {
                         state.me.displayUID = uid
                         state.me.uid = uid // 同步更新uid
                         state.me.isFirstLoad = true
+                        debugInfoSync("   🔄 更新MeFeature状态，uid: \(uid)")
                     }
-                    return .send(.me(.onAppear))
+                    
+                    // 如果当前选中的是 MeView 标签页，则触发数据加载
+                    if state.selectedTab == .other {
+                        debugInfoSync("   📱 当前在MeView，触发数据加载")
+                        return .send(.me(.onAppear))
+                    }
+                    
+                    // 如果当前选中的是 FeedView 标签页，则触发数据加载
+                    if state.selectedTab == .feed {
+                        debugInfoSync("   📱 当前在FeedView，触发数据加载")
+                        return .send(.feedList(.checkAuthAndLoad))
+                    }
+                } else {
+                    debugInfoSync("   ⚠️ AccountModel中uid无效")
                 }
                 return .none
             case .me(.settingButtonTapped):