[8.14] [Obs AI Assistant] Handle Axios errors correctly (#186790) (#1…

…86865)

# Backport

This will backport the following commits from `main` to `8.14`:
- [[Obs AI Assistant] Handle Axios errors correctly
(#186790)](#186790)

<!--- Backport version: 9.4.3 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Dario
Gieselaar","email":"dario.gieselaar@elastic.co"},"sourceCommit":{"committedDate":"2024-06-25T06:38:22Z","message":"[Obs
AI Assistant] Handle Axios errors correctly (#186790)\n\nthe `kibana`
function throws an axios error, and it resulted in an error\r\nbecause
`toJSON()` doesn't actually return a string like I expected it\r\nto, it
returns a structured object that can be converted into a string\r\nby
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AI Assistant] Handle Axios errors
correctly","number":186790,"url":"#186790
AI Assistant] Handle Axios errors correctly (#186790)\n\nthe `kibana`
function throws an axios error, and it resulted in an error\r\nbecause
`toJSON()` doesn't actually return a string like I expected it\r\nto, it
returns a structured object that can be converted into a string\r\nby
calling
JSON.stringify().","sha":"ca41e6685ea245ea8d7fb3f39b31fa18f5134821"}},"sourceBranch":"main","suggestedTargetBranches":["8.14"],"targetPullRequestStates":[{"branch":"main","label":"v8.15.0","branchLabelMappingKey":"^v8.15.0$","isSourceBranch":true,"state":"MERGED","url":"#186790
AI Assistant] Handle Axios errors correctly (#186790)\n\nthe `kibana`
function throws an axios error, and it resulted in an error\r\nbecause
`toJSON()` doesn't actually return a string like I expected it\r\nto, it
returns a structured object that can be converted into a string\r\nby
calling
JSON.stringify().","sha":"ca41e6685ea245ea8d7fb3f39b31fa18f5134821"}},{"branch":"8.14","label":"v8.14.2","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"}]}]
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Co-authored-by: Dario Gieselaar <dario.gieselaar@elastic.co>

x-pack/plugins/observability_solution/observability_ai_assistant/server/service/util/create_server_side_function_response_error.ts

@@ -6,6 +6,7 @@
  */
 
 import { errors } from '@elastic/elasticsearch';
+import { isAxiosError } from 'axios';
 import { createFunctionResponseMessage } from '../../../common/utils/create_function_response_message';
 
 export function createServerSideFunctionResponseError({
@@ -19,15 +20,18 @@ export function createServerSideFunctionResponseError({
 }) {
   const isElasticsearchError = error instanceof errors.ElasticsearchClientError;
 
-  const sanitizedError: Record<string, unknown> = JSON.parse(
-    'toJSON' in error && typeof error.toJSON === 'function' ? error.toJSON() : JSON.stringify(error)
-  );
+  const sanitizedError: Record<string, unknown> = JSON.parse(JSON.stringify(error));
 
   if (isElasticsearchError) {
     // remove meta key which is huge and noisy
     delete sanitizedError.meta;
+  } else if (isAxiosError(error)) {
+    sanitizedError.response = { message: error.response?.data?.message };
+    delete sanitizedError.config;
   }
 
+  delete sanitizedError.stack;
+
   return createFunctionResponseMessage({
     name,
     content: {