Feat: Delete dataset level graph. (#17474)

### Summary

Feat: Delete dataset level graph.

web/src/locales/en.ts

@@ -537,6 +537,7 @@ Example: A 1 KB message with 1024-dim embedding uses ~9 KB. The 5 MB default lim
       noStructureTimeline: 'No timeline yet',
       noStructureSessionEssence: 'No session essence yet',
       noStructureSessionGraph: 'No session graph yet',
+      deleteStructureConfirm: 'Are you sure you want to delete the {{name}}?',
       contents: 'Navigation',
       topics: 'Topics',
       concept: 'Concept',

web/src/locales/zh.ts

@@ -482,6 +482,7 @@ export default {
       noStructureTimeline: '暂无时间线',
       noStructureSessionEssence: '暂无会话摘要',
       noStructureSessionGraph: '暂无会话图谱',
+      deleteStructureConfirm: '确定要删除{{name}}吗？',
       contents: '导航',
       topics: '主题',
       concept: '概念',