refactor(ui): 系统代理暂停与不可读文案收成单一呈现常量

ShadowsocksX-NG2/App/ErrorPresentation+Runtime.swift

@@ -3,6 +3,12 @@ import Foundation
 // MARK: - 运行时失败事实的呈现（RuntimeFailureFacts / 系统代理应用态）
 
 extension AppPresentation {
+  /// 系统代理暂停的统一文案：状态菜单、运行控制卡与错误呈现边三面共用。
+  static let systemProxyPausedNotice = "后台代理不可用，已清除系统代理配置。恢复后将自动应用。"
+
+  /// 系统代理配置不可读的统一前缀：状态菜单与运行控制卡差异区共用。
+  static let systemProxyUnreadablePrefix = "无法读取网络接口的代理配置："
+
   static func message(for failure: RuntimeFailureFacts) -> String {
     switch failure {
     case .firewallBlocked(let facts):
@@ -27,7 +33,7 @@ extension AppPresentation {
     case .changed: return "系统代理配置已改变"
     case .applying: return "系统代理应用中"
     case .repairing: return "系统代理修复中"
-    case .paused: return "后台代理不可用，已清除系统代理配置。恢复后将自动应用。"
+    case .paused: return systemProxyPausedNotice
     }
   }
 

ShadowsocksX-NG2/App/RuntimeControlCard.swift

@@ -103,7 +103,7 @@ struct RuntimeControlCard: View {
     case .failed, .repairFailed, .clearFailed:
       "操作失败，原因见下方"
     case .paused:
-      "后台代理不可用，已清除系统代理配置。恢复后将自动应用。"
+      AppPresentation.systemProxyPausedNotice
     case .changed:
       "当前系统代理配置与预期存在差异"
     case .unreadable:
@@ -146,7 +146,8 @@ private struct SystemProxyDifferenceView: View {
         control.snapshot.systemProxyApplication != .unreadable(failure)
       {
         Text(
-          "无法读取网络接口的代理配置：\(AppPresentation.message(for: RuntimeFailureFacts.systemProxy(failure)))"
+          AppPresentation.systemProxyUnreadablePrefix
+            + AppPresentation.message(for: RuntimeFailureFacts.systemProxy(failure))
         )
         .font(.caption)
         .foregroundStyle(.orange)

ShadowsocksX-NG2/App/StatusMenuModel.swift

@@ -97,11 +97,12 @@ enum StatusMenuModel {
     case .applying: return ("应用中", nil)
     case .repairing: return ("修复中", nil)
     case .paused:
-      return ("已暂停", "后台代理不可用，已清除系统代理配置。恢复后将自动应用。")
+      return ("已暂停", AppPresentation.systemProxyPausedNotice)
     case .unreadable(let facts):
       return (
         "无法检查",
-        "无法读取网络接口的代理配置：\(AppPresentation.message(for: RuntimeFailureFacts.systemProxy(facts)))"
+        AppPresentation.systemProxyUnreadablePrefix
+          + AppPresentation.message(for: RuntimeFailureFacts.systemProxy(facts))
       )
     case .repairFailed(let facts):
       return (