fix: validate LLM work experience squash result (#4059)

Signed-off-by: Yeganathan S <63534555+skwowet@users.noreply.github.com>

Author: skwowet

services/apps/members_enrichment_worker/src/activities/llm.ts

@@ -327,7 +327,7 @@ export async function squashWorkExperiencesWithLLM(
             "startDate": "2020-06-01",
             "endDate": "2021-12-31",
             "source": "LinkedIn"
-          }
+          },
           {
             "name": "Company Y",
             "title": "Manager",
@@ -338,8 +338,7 @@ export async function squashWorkExperiencesWithLLM(
         ]
   
         Ensure the response is a **valid and complete JSON**.
-        DO NOT output anything else.
-        Output ONLY valid JSON
+        Output ONLY valid JSON array. DO NOT output anything else.
     `
 
   const llmService = new LlmService(
@@ -351,8 +350,15 @@ export async function squashWorkExperiencesWithLLM(
     svc.log,
   )
 
-  const result = await llmService.squashWorkExperiencesFromMultipleSources<
+  const res = await llmService.squashWorkExperiencesFromMultipleSources<
     IMemberEnrichmentDataNormalizedOrganization[]
   >(memberId, prompt)
-  return result.result
+
+  if (!Array.isArray(res?.result)) {
+    const errorMessage = 'LLM returned invalid work experiences payload shape!'
+    svc.log.warn({ memberId, result: res?.result }, errorMessage)
+    throw new Error(errorMessage)
+  }
+
+  return res.result
 }