feat: Refactor AppShell and Header components, enhance memory management UI, and align API endpoints

- Removed defaultCollapsed prop from AppShell and set sidebar to be collapsed by default.
- Updated Header component to remove mobile menu toggle and added a history entry button.
- Refactored ExplorationsSection to streamline data extraction and improve UI rendering.
- Added new messages for GitHub sync success and error handling in issues.
- Implemented View Memory Dialog for better memory content viewing and editing.
- Enhanced FlowToolbar to auto-create flows and improved save functionality.
- Conducted a frontend audit for API endpoint alignment with backend implementations.

ccw/frontend/src/locales/zh/issues.json

@@ -25,6 +25,10 @@
     "markResolved": "标记为已解决",
     "github": "从 GitHub 拉取"
   },
+  "messages": {
+    "githubSyncSuccess": "GitHub 同步完成：新增 {imported}、更新 {updated}、跳过 {skipped}。",
+    "githubSyncError": "GitHub 同步失败"
+  },
   "filters": {
     "all": "全部",
     "open": "开放",
@@ -147,7 +151,6 @@
     "groups": "组",
     "parallel": "并行",
     "sequential": "顺序",
-    "emptyState": "无队列数据",
     "empty": "无数据",
     "conflicts": "队列中检测到冲突",
     "noQueueData": "无队列数据",