fix(backup): add user-state backup UI and storage

locales/zh-CN.json

@@ -263,6 +263,7 @@
             "videoSettings": "视频设置",
             "layoutSettings": "布局设置",
             "misc": "其他",
+            "backup": "备份",
             "folderSettings": "默认根目录",
             "recipeSettings": "配方",
             "extraFolderPaths": "额外文件夹路径",
@@ -324,6 +325,31 @@
                 "saveFailed": "无法保存跳过路径：{message}"
             }
         },
+        "backup": {
+            "autoEnabled": "自动备份",
+            "autoEnabledHelp": "每天创建一次本地快照，并按保留策略保留最新快照。",
+            "retention": "保留数量",
+            "retentionHelp": "在删除旧快照之前，要保留多少个自动快照。",
+            "management": "备份管理",
+            "managementHelp": "导出当前用户状态，或从备份归档中恢复。",
+            "locationSummary": "当前备份位置",
+            "openFolderButton": "打开备份文件夹",
+            "openFolderSuccess": "已打开备份文件夹",
+            "openFolderFailed": "无法打开备份文件夹",
+            "locationCopied": "备份路径已复制到剪贴板：{{path}}",
+            "locationClipboardFallback": "备份路径：{{path}}",
+            "exportButton": "导出备份",
+            "exportSuccess": "备份导出成功。",
+            "exportFailed": "备份导出失败：{message}",
+            "importButton": "导入备份",
+            "importConfirm": "导入此备份并覆盖本地用户状态吗？",
+            "importSuccess": "备份导入成功。",
+            "importFailed": "备份导入失败：{message}",
+            "latestSnapshot": "最近快照",
+            "latestAutoSnapshot": "最近自动快照",
+            "snapshotCount": "已保存快照",
+            "noneAvailable": "还没有快照"
+        },
         "downloadSkipBaseModels": {
             "label": "跳过这些基础模型的下载",
             "help": "适用于所有下载流程。这里只能选择受支持的基础模型。",