chore: throw error when no search results found

i18n/en.json

@@ -92,7 +92,8 @@
     "nodeFailed": "Search failed",
     "nodeFailedToast": "Search node \"{label}\" failed",
     "followUpQuestions": "Follow-up Questions",
-    "retry": "Retry"
+    "retry": "Retry",
+    "noSearchResult": "No search results found"
   },
   "researchReport": {
     "title": "4. Research Report",

i18n/nl.json

@@ -92,7 +92,8 @@
     "nodeFailed": "Zoeken mislukt",
     "nodeFailedToast": "Zoekknooppunt \"{label}\" is mislukt",
     "followUpQuestions": "Vervolgvragen",
-    "retry": "Opnieuw proberen"
+    "retry": "Opnieuw proberen",
+    "noSearchResult": "Geen zoekresultaten gevonden"
   },
   "researchReport": {
     "title": "4. Onderzoeksrapport",

i18n/zh.json

@@ -92,7 +92,8 @@
     "nodeFailed": "搜索失败",
     "nodeFailedToast": "搜索步骤 “{label}” 失败",
     "followUpQuestions": "后续问题",
-    "retry": "重试"
+    "retry": "重试",
+    "noSearchResult": "未找到搜索结果"
   },
   "researchReport": {
     "title": "4. 研究报告",