完善样片管理列表、详情与上传页 UI 交互。

对齐 Android 样片模块布局与加载状态，补充共享 UI 组件与图片资源，并增强列表解析容错与单元测试覆盖。

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

suixinkan/Features/SampleManagement/ViewModels/SampleManagementViewModels.swift

@@ -26,6 +26,7 @@ final class SampleListViewModel {
     private(set) var canLoadMore = false
     private(set) var filterStatus: SampleFilterStatus = .all
     private(set) var searchText = ""
+    private(set) var operatingSampleIDs: Set<Int> = []
 
     var onStateChange: (() -> Void)?
     var onShowMessage: ((String) -> Void)?
@@ -33,6 +34,11 @@ final class SampleListViewModel {
     private var currentPage = 1
     private var totalCount = 0
     private let pageSize = 10
+    private var isRequestingList = false
+    private var isLoadingMore = false
+
+    /// 是否正在执行样片上下架操作。
+    var isOperating: Bool { !operatingSampleIDs.isEmpty }
 
     /// 首次加载样片列表。
     func loadInitial(api: any SampleManagementServing) async {
@@ -67,15 +73,26 @@ final class SampleListViewModel {
     }
 
     /// 切换样片上下架状态。
-    func toggleListing(sampleId: Int, checked: Bool, api: any SampleManagementServing) async {
-        guard let currentItem = items.first(where: { $0.id == sampleId }) else { return }
+    @discardableResult
+    func toggleListing(sampleId: Int, checked: Bool, api: any SampleManagementServing) async -> Bool {
+        guard let currentItem = items.first(where: { $0.id == sampleId }) else { return !checked }
+        let previousState = currentItem.isListed
         guard currentItem.status == 1 else {
             onShowMessage?("审核通过才可以操作上下架")
-            return
+            notifyStateChange()
+            return previousState
         }
 
         let targetStatus = checked ? 1 : 0
-        guard currentItem.listingStatus != targetStatus else { return }
+        guard currentItem.listingStatus != targetStatus else { return previousState }
+
+        guard !operatingSampleIDs.contains(sampleId) else { return previousState }
+        operatingSampleIDs.insert(sampleId)
+        notifyStateChange()
+        defer {
+            operatingSampleIDs.remove(sampleId)
+            notifyStateChange()
+        }
 
         do {
             try await api.setListingStatus(id: sampleId, listingStatus: targetStatus)
@@ -97,25 +114,38 @@ final class SampleListViewModel {
                 )
             }
             notifyStateChange()
+            return checked
         } catch is CancellationError {
-            return
+            return previousState
         } catch {
             onShowMessage?(error.localizedDescription.isEmpty ? "操作失败" : error.localizedDescription)
+            return previousState
         }
     }
 
     private func load(reset: Bool, showLoading: Bool, api: any SampleManagementServing) async {
+        guard !isRequestingList else {
+            if isRefreshing {
+                isRefreshing = false
+                notifyStateChange()
+            }
+            return
+        }
         if reset {
             currentPage = 1
             canLoadMore = false
         } else {
-            guard canLoadMore, !isLoading else { return }
+            guard canLoadMore, !isLoading, !isLoadingMore else { return }
+            isLoadingMore = true
             currentPage += 1
         }
 
+        isRequestingList = true
         isLoading = showLoading
         notifyStateChange()
         defer {
+            isRequestingList = false
+            if !reset { isLoadingMore = false }
             isLoading = false
             isRefreshing = false
             notifyStateChange()
@@ -276,7 +306,7 @@ final class UploadSampleViewModel {
             onShowMessage?("请先选择景区")
             return
         }
-        if projectIsLoading && !refresh { return }
+        guard !projectIsLoading else { return }
         if refresh {
             projectCurrentPage = 1
             projectList = []