refactor(qrcode): 优化二维码转文本布局，与文本转二维码风格统一

- 未上传图片时只显示上传区域
- 上传图片后显示小图预览 + 解析结果
- 添加重新上传按钮
- 解析结果文本限制显示长度
- 新增国际化文案（已上传图片、重新上传、解析中等）
- 适配popup窗口紧凑布局

public/_locales/zh/messages.json

@@ -600,6 +600,22 @@
     "message": "生成二维码失败，请重试",
     "description": "Translation key: qrCode_generateError"
   },
+  "qrCode_uploadedImage": {
+    "message": "已上传图片",
+    "description": "Translation key: qrCode_uploadedImage"
+  },
+  "qrCode_reuploadButton": {
+    "message": "重新上传",
+    "description": "Translation key: qrCode_reuploadButton"
+  },
+  "qrCode_parsing": {
+    "message": "解析中...",
+    "description": "Translation key: qrCode_parsing"
+  },
+  "qrCode_resultPlaceholder": {
+    "message": "解析结果将显示在此处",
+    "description": "Translation key: qrCode_resultPlaceholder"
+  },
   "rightClickRestorer_loading": {
     "message": "正在加载...",
     "description": "Translation key: rightClickRestorer_loading"