refactor(ui): 系统代理失败文案映射三份收成一份

ShadowsocksX-NG2/App/ErrorPresentation+Runtime.swift

@@ -58,8 +58,10 @@ extension AppPresentation {
     }
   }
 
+  // 系统代理操作失败的唯一文案映射（ErrorPresentation 的 SystemProxyError
+  // 分支经 SystemProxyOperationFailure(error) 桥接到这里）。
   // swiftlint:disable:next cyclomatic_complexity
-  private static func systemProxy(_ failure: SystemProxyOperationFailure) -> String {
+  static func systemProxy(_ failure: SystemProxyOperationFailure) -> String {
     switch failure {
     case .preferencesUnavailable: return "系统网络配置不可用"
     case .preferencesBusy: return "系统网络配置正被其他设置操作占用"

ShadowsocksX-NG2/App/ErrorPresentation.swift

@@ -60,7 +60,7 @@ extension AppPresentation {
     case let error as LegacyImportError:
       return legacyImport(error)
     case let error as SystemProxyError:
-      return systemProxy(error)
+      return systemProxy(SystemProxyOperationFailure(error))
     case let error as TextClipboardFailure:
       return textClipboard(error)
     case let error as DiagnosticReportFailure:
@@ -305,24 +305,6 @@ extension AppPresentation {
     }
   }
 
-  // swiftlint:disable:next cyclomatic_complexity
-  private static func systemProxy(_ error: SystemProxyError) -> String {
-    switch error {
-    case .preferencesUnavailable: return "系统网络配置不可用"
-    case .preferencesBusy: return "系统网络配置正被其他设置操作占用"
-    case .noCurrentNetworkSet: return "没有当前网络位置"
-    case .noNetworkLocations: return "没有可检查的网络位置"
-    case .noProxyServices: return "当前网络位置没有可写入的网络服务"
-    case .unreadableService: return "无法读取网络服务的代理配置"
-    case .invalidStoredConfiguration: return "保存的系统代理配置无效"
-    case .cannotWriteService: return "无法写入网络服务的代理配置"
-    case .commitFailed: return "系统代理提交失败"
-    case .applyFailed: return "系统代理应用失败"
-    case .invalidRequest: return "系统代理助手收到了无效请求"
-    case .helperUnavailable: return "系统代理助手不可用；请确认已在登录项中允许"
-    }
-  }
-
   private static func textClipboard(_ error: TextClipboardFailure) -> String {
     switch error {
     case .writeFailed: return "剪贴板写入失败，请重试"

ShadowsocksX-NG2/App/ProxyRuntimeFacts.swift

@@ -111,6 +111,27 @@ enum SystemProxyOperationFailure: Equatable, Sendable {
   case helperUnavailable
 }
 
+extension SystemProxyOperationFailure {
+  /// `SystemProxyError` 的呈现类别投影：稳定事实只保留操作类别；Domain 错误
+  /// 的关联值（排查细节）不出现在运行时事实里。
+  init(_ error: SystemProxyError) {
+    switch error {
+    case .preferencesUnavailable: self = .preferencesUnavailable
+    case .preferencesBusy: self = .preferencesBusy
+    case .noCurrentNetworkSet: self = .noCurrentNetworkSet
+    case .noNetworkLocations: self = .noNetworkLocations
+    case .noProxyServices: self = .noProxyServices
+    case .unreadableService: self = .unreadableService
+    case .invalidStoredConfiguration: self = .invalidStoredConfiguration
+    case .cannotWriteService: self = .cannotWriteService
+    case .commitFailed: self = .commitFailed
+    case .applyFailed: self = .applyFailed
+    case .invalidRequest: self = .invalidRequest
+    case .helperUnavailable: self = .helperUnavailable
+    }
+  }
+}
+
 enum SystemProxyFailureFacts: Equatable, Sendable {
   case operation(SystemProxyOperationFailure)
   case mode(ProxyModeError)

ShadowsocksX-NG2/App/SystemProxyObserver.swift

@@ -472,32 +472,11 @@ extension SystemProxyObserver {
 extension SystemProxyObserver {
   private func systemProxyFacts(for error: Error) -> SystemProxyFailureFacts {
     if let error = error as? SystemProxyError {
-      return Self.systemProxyFacts(for: error)
+      return .operation(SystemProxyOperationFailure(error))
     }
     if let error = error as? ProxyModeError {
       return .mode(error)
     }
     return .unknown
   }
-
-  // 显式映射保持与错误族一一对应；错误带关联值，无法用字典键穷举。
-  // swiftlint:disable:next cyclomatic_complexity
-  private static func systemProxyFacts(
-    for error: SystemProxyError
-  ) -> SystemProxyFailureFacts {
-    switch error {
-    case .preferencesUnavailable: return .operation(.preferencesUnavailable)
-    case .preferencesBusy: return .operation(.preferencesBusy)
-    case .noCurrentNetworkSet: return .operation(.noCurrentNetworkSet)
-    case .noProxyServices: return .operation(.noProxyServices)
-    case .unreadableService: return .operation(.unreadableService)
-    case .invalidStoredConfiguration: return .operation(.invalidStoredConfiguration)
-    case .cannotWriteService: return .operation(.cannotWriteService)
-    case .commitFailed: return .operation(.commitFailed)
-    case .applyFailed: return .operation(.applyFailed)
-    case .noNetworkLocations: return .operation(.noNetworkLocations)
-    case .invalidRequest: return .operation(.invalidRequest)
-    case .helperUnavailable: return .operation(.helperUnavailable)
-    }
-  }
 }