feat(devices): 设备默认名「平台简写·主机名」+ 支持重命名(1.0.13)

① 默认名:DeviceIdentity 改「平台简写(Win/Mac/Linux/iOS/Andr)·主机名」,主机名截
   到 8、总长≈12(替代裸主机名,更短)。
② 重命名:新端点 POST /v1/me/devices/{uuid}/rename(Service.RenameDevice 校验归属+
   截 64);store.UpdateName;客户端 account_api.renameDevice + provider.rename +
   「我的设备」⋯ 菜单加「重命名」+ 输入弹窗;l10n(zh/en)。
③ 版本 1.0.13。
测试:server RenameDevice(归属/空名/404)+ 客户端 rename widget;全量 go/flutter 绿。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/l10n/app_text.dart

@@ -95,6 +95,9 @@ abstract class AppText {
   String get devNeverLogin;
   String get devForceLogout;
   String get devClearLogin;
+  String get devRename;
+  String get devRenameHint;
+  String get devSave;
   String get devForceLogoutConfirm; // 弹窗正文(含设备名占位 %s)
   String get devClearLoginConfirm;
   String get devCancel;

client/lib/l10n/strings_en.dart

@@ -140,6 +140,12 @@ class StringsEn extends AppText {
   @override
   String get devClearLogin => 'Clear login info';
   @override
+  String get devRename => 'Rename';
+  @override
+  String get devRenameHint => 'Device name';
+  @override
+  String get devSave => 'Save';
+  @override
   String get devForceLogoutConfirm => 'This revokes the device\'s login session — it will be kicked offline and must sign in again. The device stays in the list.';
   @override
   String get devClearLoginConfirm => 'This removes the device from the list entirely and revokes its login session and data-plane credential. The device must sign in again to be used.';

client/lib/l10n/strings_zh.dart

@@ -139,6 +139,12 @@ class StringsZh extends AppText {
   @override
   String get devClearLogin => '清除登录信息';
   @override
+  String get devRename => '重命名';
+  @override
+  String get devRenameHint => '设备名称';
+  @override
+  String get devSave => '保存';
+  @override
   String get devForceLogoutConfirm => '将吊销该设备的登录会话,它会被踢下线、需重新登录。设备仍保留在列表中。';
   @override
   String get devClearLoginConfirm => '将从设备列表彻底移除此设备,并吊销其登录会话与数据面凭证。该设备需重新登录才能再次使用。';