FIX: Resolve keyboard shortcuts and enhance image preview with i18n support

- Fix keyboard shortcut conflicts in FileViewer.tsx (Ctrl+F, H, ?, Space, A)
- Add comprehensive i18n translations for keyboard shortcuts help panel
- Integrate react-photo-view for enhanced fullscreen image viewing
- Simplify image preview by removing complex toolbar and hover hints
- Add proper error handling and loading states for image display
- Update English and Chinese translation files with new keyboard shortcut terms

🤖 Generated with [Claude Code](https://claude.ai/code)

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

src/locales/zh/translation.json

@@ -880,6 +880,30 @@
     "replace": "替换",
     "replaceAll": "全部替换",
     "downloadInstead": "下载文件",
+    "keyboardShortcuts": "键盘快捷键",
+    "searchAndReplace": "搜索和替换",
+    "editing": "编辑",
+    "navigation": "导航",
+    "code": "代码",
+    "search": "搜索",
+    "findNext": "查找下一个",
+    "findPrevious": "查找上一个",
+    "save": "保存",
+    "selectAll": "全选",
+    "undo": "撤销",
+    "redo": "重做",
+    "goToLine": "跳转到行",
+    "moveLineUp": "向上移动行",
+    "moveLineDown": "向下移动行",
+    "toggleComment": "切换注释",
+    "indent": "增加缩进",
+    "outdent": "减少缩进",
+    "autoComplete": "自动补全",
+    "imageLoadError": "图片加载失败",
+    "zoomIn": "放大",
+    "zoomOut": "缩小",
+    "rotate": "旋转",
+    "originalSize": "原始大小",
     "startTyping": "开始输入...",
     "fileSavedSuccessfully": "文件保存成功",
     "autoSaveFailed": "自动保存失败",