feat: Fetch mind map in search page #2247 (#2292)

### What problem does this PR solve?
feat: Fetch mind map in search page #2247

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/utils/api.ts

@@ -68,6 +68,7 @@ export default {
   tts: `${api_host}/conversation/tts`,
   ask: `${api_host}/conversation/ask`,
   mindmap: `${api_host}/conversation/mindmap`,
+  getRelatedQuestions: `${api_host}/conversation/related_questions`,
   // chat for external
   createToken: `${api_host}/api/new_token`,
   listToken: `${api_host}/api/token_list`,