release(ios): 发布 0.2.1 并重构图标与界面细节

- 应用图标改用与 Web favicon 同源的扁平标记，金色 SIM 卡体加三格递增信号，29pt 下仍可读
- 标签统一为胶囊形状，提高深色主题下的描边权重，避免标签在暗色下消失
- 消息卡片与详情分区卡片收紧行距，单屏信息密度明显提升
- 详情头部指标精简为 4 行，数据模块改为单条读数
- 批量选择勾选框移出名称区域，工具栏控件统一为等高 34pt
- 分组编辑器改为点选即生效，移除说明文字与常驻禁用按钮

apps/ios/Sources/MultiSimAdmin/Features/Settings/SettingsViewModel.swift

@@ -1,12 +1,14 @@
 import Foundation
-import Darwin
+#if canImport(UIKit)
+  import UIKit
+#endif
 
 struct SettingsRuntime: Equatable {
     let appName: String
     let marketingVersion: String
     let buildVersion: String
     let platform: String
-    let deviceModel: String
+    let systemVersion: String
 }
 
 @MainActor
@@ -32,7 +34,7 @@ final class SettingsViewModel: ObservableObject {
             marketingVersion: AppMetadata.marketingVersion,
             buildVersion: AppMetadata.buildVersion,
             platform: "iOS",
-            deviceModel: Self.deviceModel()
+            systemVersion: Self.systemVersion()
         )
         await loadStorageLabel()
 
@@ -64,14 +66,14 @@ final class SettingsViewModel: ObservableObject {
         }
     }
 
-    private static func deviceModel() -> String {
-        var systemInfo = utsname()
-        guard uname(&systemInfo) == 0 else { return "未知设备" }
-        let bytes = withUnsafeBytes(of: systemInfo.machine) { Data($0) }
-        let model = String(
-            decoding: bytes.prefix { $0 != 0 },
-            as: UTF8.self
-        )
-        return model.isEmpty ? "未知设备" : model
+    /// 只报对用户有意义的系统版本，不暴露机器标识之类的原始信息。
+    private static func systemVersion() -> String {
+        #if canImport(UIKit)
+          let device = UIDevice.current
+          return "\(device.systemName) \(device.systemVersion)"
+        #else
+          let version = ProcessInfo.processInfo.operatingSystemVersion
+          return "iOS \(version.majorVersion).\(version.minorVersion)"
+        #endif
     }
 }