fix: 安全审查 P3 问题修复（10项）

无障碍与用户体验：
- 补全 OnboardingView/ProcessingView/ResultView/WallpaperGuideView 无障碍标注
- ContentView 添加后台切换截屏保护（模糊覆盖层）
- EditorView iPad 右侧面板改为响应式宽度（minWidth:320, maxWidth:420）
- ResultView CelebrationParticles 改用 Task 替代 DispatchQueue 延迟
- DesignSystem accessibility key 从中文改为英文
- EditorView/WallpaperGuideView 生成按钮 accentColor 统一为设计系统
- OnboardingView 第四页添加相册权限预告提示

核心库优化：
- LivePhotoLogger 添加日志安全注释
- CacheManager.makeWorkPaths 添加磁盘空间预检查（<500MB 报错）
- ImageFormatConverter BGRA/ARGB 转换改用 vImagePermuteChannels 加速

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Sources/LivePhotoCore/AIEnhancer/ImageFormatConverter.swift

@@ -212,21 +212,25 @@ enum ImageFormatConverter {
         bytesPerRow: Int
     ) -> [UInt8] {
         var result = [UInt8](repeating: 0, count: width * height * 4)
+        let dstBytesPerRow = width * 4
 
-        for y in 0..<height {
+        var srcBuffer = vImage_Buffer(
-            let srcRow = baseAddress.advanced(by: y * bytesPerRow).assumingMemoryBound(to: UInt8.self)
+            data: baseAddress,
-            let dstOffset = y * width * 4
+            height: vImagePixelCount(height),
+            width: vImagePixelCount(width),
+            rowBytes: bytesPerRow
+        )
 
-            for x in 0..<width {
+        result.withUnsafeMutableBufferPointer { dstPtr in
-                let srcIdx = x * 4
+            var dstBuffer = vImage_Buffer(
-                let dstIdx = dstOffset + x * 4
+                data: dstPtr.baseAddress!,
-
+                height: vImagePixelCount(height),
-                // BGRA -> RGBA swap
+                width: vImagePixelCount(width),
-                result[dstIdx + 0] = srcRow[srcIdx + 2]  // R
+                rowBytes: dstBytesPerRow
-                result[dstIdx + 1] = srcRow[srcIdx + 1]  // G
+            )
-                result[dstIdx + 2] = srcRow[srcIdx + 0]  // B
+            // BGRA → RGBA: 通道重排 [2,1,0,3]
-                result[dstIdx + 3] = srcRow[srcIdx + 3]  // A
+            let permuteMap: [UInt8] = [2, 1, 0, 3]
-            }
+            vImagePermuteChannels_ARGB8888(&srcBuffer, &dstBuffer, permuteMap, vImage_Flags(kvImageNoFlags))
         }
 
         return result
@@ -239,21 +243,25 @@ enum ImageFormatConverter {
         bytesPerRow: Int
     ) -> [UInt8] {
         var result = [UInt8](repeating: 0, count: width * height * 4)
+        let dstBytesPerRow = width * 4
 
-        for y in 0..<height {
+        var srcBuffer = vImage_Buffer(
-            let srcRow = baseAddress.advanced(by: y * bytesPerRow).assumingMemoryBound(to: UInt8.self)
+            data: baseAddress,
-            let dstOffset = y * width * 4
+            height: vImagePixelCount(height),
+            width: vImagePixelCount(width),
+            rowBytes: bytesPerRow
+        )
 
-            for x in 0..<width {
+        result.withUnsafeMutableBufferPointer { dstPtr in
-                let srcIdx = x * 4
+            var dstBuffer = vImage_Buffer(
-                let dstIdx = dstOffset + x * 4
+                data: dstPtr.baseAddress!,
-
+                height: vImagePixelCount(height),
-                // ARGB -> RGBA swap
+                width: vImagePixelCount(width),
-                result[dstIdx + 0] = srcRow[srcIdx + 1]  // R
+                rowBytes: dstBytesPerRow
-                result[dstIdx + 1] = srcRow[srcIdx + 2]  // G
+            )
-                result[dstIdx + 2] = srcRow[srcIdx + 3]  // B
+            // ARGB → RGBA: 通道重排 [1,2,3,0]
-                result[dstIdx + 3] = srcRow[srcIdx + 0]  // A
+            let permuteMap: [UInt8] = [1, 2, 3, 0]
-            }
+            vImagePermuteChannels_ARGB8888(&srcBuffer, &dstBuffer, permuteMap, vImage_Flags(kvImageNoFlags))
         }
 
         return result

Sources/LivePhotoCore/LivePhotoCore.swift

@@ -260,6 +260,18 @@ public struct CacheManager: Sendable {
     }
 
     public func makeWorkPaths(workId: UUID) throws -> LivePhotoWorkPaths {
+        // 检查可用磁盘空间（视频处理需要约 500MB 临时空间）
+        let resourceValues = try baseDirectory.resourceValues(forKeys: [.volumeAvailableCapacityForImportantUsageKey])
+        if let availableCapacity = resourceValues.volumeAvailableCapacityForImportantUsage,
+           availableCapacity < 500_000_000 {
+            throw AppError(
+                code: "LPB-001",
+                stage: .normalize,
+                message: String(localized: "error.insufficientDiskSpace"),
+                suggestedActions: [String(localized: "error.clearCache"), String(localized: "error.freeSpace")]
+            )
+        }
+
         let workDir = baseDirectory.appendingPathComponent(workId.uuidString, isDirectory: true)
         try FileManager.default.createDirectory(at: workDir, withIntermediateDirectories: true)
         return LivePhotoWorkPaths(
@@ -291,10 +303,14 @@ public struct LivePhotoLogger: Sendable {
         self.logger = os.Logger(subsystem: subsystem, category: category)
     }
 
+    /// 记录信息级别日志
+    /// - Important: 日志使用 .public 隐私级别，不要在消息中包含用户输入内容、个人信息或文件路径中的用户名
     public func info(_ message: String) {
         logger.info("\(message, privacy: .public)")
     }
 
+    /// 记录错误级别日志
+    /// - Important: 日志使用 .public 隐私级别，不要在消息中包含用户输入内容、个人信息或文件路径中的用户名
     public func error(_ message: String) {
         logger.error("\(message, privacy: .public)")
     }

to-live-photo/to-live-photo/ContentView.swift

@@ -10,32 +10,58 @@ import LivePhotoCore
 
 struct ContentView: View {
     @Environment(AppState.self) private var appState
+    @Environment(\.scenePhase) private var scenePhase
     @AppStorage("hasCompletedOnboarding") private var hasCompletedOnboarding = false
+    @State private var showPrivacyOverlay = false
 
     var body: some View {
         @Bindable var appState = appState
 
-        if !hasCompletedOnboarding {
+        ZStack {
-            OnboardingView(hasCompletedOnboarding: $hasCompletedOnboarding)
+            if !hasCompletedOnboarding {
-        } else {
+                OnboardingView(hasCompletedOnboarding: $hasCompletedOnboarding)
-            NavigationStack(path: $appState.navigationPath) {
+            } else {
-                HomeView()
+                NavigationStack(path: $appState.navigationPath) {
-                    .navigationDestination(for: AppRoute.self) { route in
+                    HomeView()
-                        switch route {
+                        .navigationDestination(for: AppRoute.self) { route in
-                        case .home:
+                            switch route {
-                            HomeView()
+                            case .home:
-                        case .editor(let videoURL):
+                                HomeView()
-                            EditorView(videoURL: videoURL)
+                            case .editor(let videoURL):
-                        case .processing(let videoURL, let exportParams):
+                                EditorView(videoURL: videoURL)
-                            ProcessingView(videoURL: videoURL, exportParams: exportParams)
+                            case .processing(let videoURL, let exportParams):
-                        case .result(let workflowResult):
+                                ProcessingView(videoURL: videoURL, exportParams: exportParams)
-                            ResultView(workflowResult: workflowResult)
+                            case .result(let workflowResult):
-                        case .wallpaperGuide(let assetId):
+                                ResultView(workflowResult: workflowResult)
-                            WallpaperGuideView(assetId: assetId)
+                            case .wallpaperGuide(let assetId):
-                        case .settings:
+                                WallpaperGuideView(assetId: assetId)
-                            SettingsView()
+                            case .settings:
+                                SettingsView()
+                            }
+                        }
+                }
+            }
+
+            // Privacy overlay for app switcher
+            if showPrivacyOverlay {
+                Color.softBackground
+                    .ignoresSafeArea()
+                    .overlay {
+                        VStack(spacing: DesignTokens.Spacing.lg) {
+                            Image(systemName: "livephoto")
+                                .font(.system(size: 48))
+                                .foregroundStyle(.tint)
+                            Text("Live Photo Studio")
+                                .font(.headline)
+                                .foregroundColor(.textSecondary)
                         }
                     }
+                    .transition(.opacity)
+            }
+        }
+        .onChange(of: scenePhase) { _, newPhase in
+            withAnimation(.easeInOut(duration: 0.2)) {
+                showPrivacyOverlay = newPhase != .active
             }
         }
     }

to-live-photo/to-live-photo/DesignSystem.swift

@@ -447,7 +447,7 @@ struct SoftProgressRing: View {
                 .animation(DesignTokens.Animation.smooth, value: progress)
         }
         .accessibilityElement(children: .ignore)
-        .accessibilityLabel(accessibilityLabel ?? String(localized: "进度"))
+        .accessibilityLabel(accessibilityLabel ?? String(localized: "accessibility.progress"))
         .accessibilityValue(Text("\(Int(progress * 100))%"))
     }
 }
@@ -593,7 +593,7 @@ struct SoftSlider: View {
         }
         .frame(height: 28)
         .accessibilityElement(children: .ignore)
-        .accessibilityLabel(accessibilityLabel.isEmpty ? String(localized: "滑块") : accessibilityLabel)
+        .accessibilityLabel(accessibilityLabel.isEmpty ? String(localized: "accessibility.slider") : accessibilityLabel)
         .accessibilityValue(Text(String(format: "%.1f", value)))
         .accessibilityAdjustableAction { direction in
             guard !isDisabled else { return }

to-live-photo/to-live-photo/Views/EditorView.swift

@@ -119,7 +119,7 @@ struct EditorView: View {
                 }
                 .padding(.vertical, DesignTokens.Spacing.lg)
             }
-            .frame(maxWidth: 360)
+            .frame(minWidth: 320, maxWidth: 420)
         }
         .padding(DesignTokens.Spacing.xxl)
     }
@@ -593,7 +593,7 @@ struct EditorView: View {
             .font(.headline)
             .frame(maxWidth: .infinity)
             .padding()
-            .background(Color.accentColor)
+            .background(Color.gradientPrimary)
             .foregroundColor(.white)
             .clipShape(RoundedRectangle(cornerRadius: 14))
         }
@@ -824,10 +824,10 @@ struct AspectRatioButton: View {
             VStack(spacing: 4) {
                 // 比例图标
                 RoundedRectangle(cornerRadius: 4)
-                    .stroke(isSelected ? Color.accentColor : Color.textSecondary, lineWidth: 2)
+                    .stroke(isSelected ? Color.accentPurple : Color.textSecondary, lineWidth: 2)
                     .frame(width: iconWidth, height: iconHeight)
                     .background(
-                        isSelected ? Color.accentColor.opacity(0.1) : Color.clear
+                        isSelected ? Color.accentPurple.opacity(0.1) : Color.clear
                     )
                     .clipShape(RoundedRectangle(cornerRadius: 4))
 
@@ -838,7 +838,7 @@ struct AspectRatioButton: View {
             }
             .frame(maxWidth: .infinity)
             .padding(.vertical, DesignTokens.Spacing.sm)
-            .background(isSelected ? Color.accentColor.opacity(0.1) : Color.clear)
+            .background(isSelected ? Color.accentPurple.opacity(0.1) : Color.clear)
             .clipShape(RoundedRectangle(cornerRadius: DesignTokens.Radius.sm))
         }
         .buttonStyle(.plain)

to-live-photo/to-live-photo/Views/OnboardingView.swift

@@ -113,6 +113,23 @@ struct OnboardingView: View {
                     .foregroundColor(.textSecondary)
                     .multilineTextAlignment(.center)
                     .lineSpacing(4)
+
+                // 第四页：相册权限预告
+                if index == 3 {
+                    HStack(spacing: 6) {
+                        Image(systemName: "lock.shield")
+                            .font(.caption)
+                            .foregroundColor(.accentGreen)
+                        Text(String(localized: "onboarding.page4.permissionHint"))
+                            .font(.caption)
+                            .foregroundColor(.textMuted)
+                            .multilineTextAlignment(.center)
+                    }
+                    .padding(.horizontal, DesignTokens.Spacing.lg)
+                    .padding(.vertical, DesignTokens.Spacing.sm)
+                    .background(Color.accentGreen.opacity(0.1))
+                    .clipShape(Capsule())
+                }
             }
             .padding(.horizontal, DesignTokens.Spacing.xxxl)
 
@@ -134,6 +151,9 @@ struct OnboardingView: View {
                         .animation(.spring(response: 0.3, dampingFraction: 0.7), value: currentPage)
                 }
             }
+            .accessibilityElement(children: .ignore)
+            .accessibilityLabel(String(localized: "accessibility.pageIndicator"))
+            .accessibilityValue(String(localized: "accessibility.pageOf \(currentPage + 1) \(pages.count)"))
             .padding(.bottom, DesignTokens.Spacing.md)
 
             // 主按钮

to-live-photo/to-live-photo/Views/ProcessingView.swift

@@ -138,6 +138,8 @@ struct ProcessingView: View {
                             .animation(.spring(response: 0.3), value: currentStageIndex)
                     }
                 }
+                .accessibilityElement(children: .ignore)
+                .accessibilityLabel(String(localized: "accessibility.processingStage"))
                 .padding(.top, DesignTokens.Spacing.md)
             }
         }

to-live-photo/to-live-photo/Views/ResultView.swift

@@ -26,6 +26,7 @@ struct ResultView: View {
             // 成功时的庆祝粒子效果
             if isSuccess && celebrationParticles {
                 CelebrationParticles()
+                    .accessibilityHidden(true)
             }
 
             VStack(spacing: DesignTokens.Spacing.xxxl) {
@@ -223,14 +224,14 @@ struct CelebrationParticles: View {
                     .position(particle.position)
                     .opacity(particle.opacity)
             }
-            .onAppear {
+            .task {
                 viewSize = geometry.size
-                generateParticles(in: geometry.size)
+                await generateParticles(in: geometry.size)
             }
         }
     }
 
-    private func generateParticles(in size: CGSize) {
+    private func generateParticles(in size: CGSize) async {
         let colors: [Color] = [.accentPurple, .accentPink, .accentGreen, .accentCyan, .accentOrange]
 
         // 使用实际屏幕尺寸计算粒子位置
@@ -241,25 +242,29 @@ struct CelebrationParticles: View {
         let flyDistance = size.height * 0.4  // 飞行距离为屏幕高度的 40%
 
         for i in 0..<30 {
-            let delay = Double(i) * 0.03
+            let delayNanoseconds = UInt64(Double(i) * 0.03 * 1_000_000_000)
 
-            DispatchQueue.main.asyncAfter(deadline: .now() + delay) {
+            do {
-                let particle = Particle(
+                try await Task.sleep(nanoseconds: delayNanoseconds)
-                    id: UUID(),
+            } catch {
-                    position: CGPoint(x: CGFloat.random(in: minX...maxX), y: startY),
+                return // Task was cancelled (view destroyed)
-                    color: colors.randomElement()!,
+            }
-                    size: CGFloat.random(in: 6...12),
-                    opacity: 1.0
-                )
-                particles.append(particle)
 
-                // 动画粒子向上飘动
+            let particle = Particle(
-                withAnimation(.easeOut(duration: Double.random(in: 1.5...2.5))) {
+                id: UUID(),
-                    if let index = particles.firstIndex(where: { $0.id == particle.id }) {
+                position: CGPoint(x: CGFloat.random(in: minX...maxX), y: startY),
-                        particles[index].position.y -= CGFloat.random(in: flyDistance...(flyDistance * 1.5))
+                color: colors.randomElement()!,
-                        particles[index].position.x += CGFloat.random(in: -50...50)
+                size: CGFloat.random(in: 6...12),
-                        particles[index].opacity = 0
+                opacity: 1.0
-                    }
+            )
+            particles.append(particle)
+
+            // 动画粒子向上飘动
+            withAnimation(.easeOut(duration: Double.random(in: 1.5...2.5))) {
+                if let index = particles.firstIndex(where: { $0.id == particle.id }) {
+                    particles[index].position.y -= CGFloat.random(in: flyDistance...(flyDistance * 1.5))
+                    particles[index].position.x += CGFloat.random(in: -50...50)
+                    particles[index].opacity = 0
                 }
             }
         }

to-live-photo/to-live-photo/Views/WallpaperGuideView.swift

@@ -225,7 +225,7 @@ struct WallpaperGuideView: View {
                     .font(.headline)
                     .frame(maxWidth: .infinity)
                     .padding()
-                    .background(Color.accentColor)
+                    .background(Color.gradientPrimary)
                     .foregroundColor(.white)
                     .clipShape(RoundedRectangle(cornerRadius: DesignTokens.Radius.md))
             }
@@ -250,7 +250,7 @@ struct StepRow: View {
             VStack(spacing: 0) {
                 ZStack {
                     Circle()
-                        .fill(Color.accentColor)
+                        .fill(Color.accentPurple)
                         .frame(width: 32, height: 32)
                     Text("\(number)")
                         .font(.subheadline)
@@ -260,7 +260,7 @@ struct StepRow: View {
                 
                 if !isLast {
                     Rectangle()
-                        .fill(Color.accentColor.opacity(0.3))
+                        .fill(Color.accentPurple.opacity(0.3))
                         .frame(width: 2)
                         .frame(maxHeight: .infinity)
                 }
@@ -275,7 +275,7 @@ struct StepRow: View {
                         .font(.subheadline)
                         .fontWeight(.semibold)
                 }
-                
+
                 Text(description)
                     .font(.caption)
                     .foregroundStyle(.secondary)
@@ -283,6 +283,7 @@ struct StepRow: View {
             }
             .padding(.bottom, isLast ? 0 : 16)
         }
+        .accessibilityElement(children: .combine)
     }
 }
 
@@ -312,6 +313,7 @@ struct FAQRow: View {
         .frame(maxWidth: .infinity, alignment: .leading)
         .background(Color.softElevated)
         .clipShape(RoundedRectangle(cornerRadius: DesignTokens.Radius.md))
+        .accessibilityElement(children: .combine)
     }
 }