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/orchestrator.json

@@ -107,7 +107,8 @@
       "searchSuggestion": "尝试不同的搜索查询"
     },
     "footer": {
-      "templateCount": "{count} 个模板"
+      "templateCount": "{count} 个模板",
+      "templateCount_plural": "{count} 个模板"
     },
     "card": {
       "nodes": "个节点",