fix(server): handle network errors in RestApiService catch block (#20644)

## Summary
- Added safe null check for `err.response?.data?.errors` in
`RestApiService.call()` catch block
- When the internal HTTP client fails with a network-level error
(ECONNREFUSED, timeout), `err.response` is `undefined` — accessing
`.data.errors` on it throws a `TypeError` which gets silently swallowed,
returning an empty 500
- Now falls back to throwing the raw error message for network failures
instead of crashing

## Changes
- `packages/twenty-server/src/engine/api/rest/rest-api.service.ts`

Fixes #20136

---------

Co-authored-by: Marie Stoppa <marie@twenty.com>

packages/twenty-server/src/engine/api/rest/rest-api.service.ts

@@ -6,6 +6,7 @@ import { type Query } from 'src/engine/api/rest/core/types/query.type';
 import { RestApiException } from 'src/engine/api/rest/errors/RestApiException';
 import { type RequestContext } from 'src/engine/api/rest/types/RequestContext';
 import { SecureHttpClientService } from 'src/engine/core-modules/secure-http-client/secure-http-client.service';
+import { isDefined } from 'twenty-shared/utils';
 
 export enum GraphqlApiType {
   CORE = 'core',
@@ -41,10 +42,14 @@ export class RestApiService {
         },
       });
     } catch (err) {
-      throw new RestApiException(err.response.data.errors);
+      if (isDefined(err.response?.data?.errors)) {
+        throw new RestApiException(err.response.data.errors);
+      }
+
+      throw err;
     }
 
-    if (response.data.errors?.length) {
+    if (isDefined(response.data.errors) && response.data.errors.length > 0) {
       throw new RestApiException(response.data.errors);
     }
 

packages/twenty-server/src/filters/unhandled-exception.filter.ts

@@ -35,6 +35,6 @@ export class UnhandledExceptionFilter implements ExceptionFilter {
     const status =
       exception instanceof HttpException ? exception.getStatus() : 500;
 
-    response.status(status).json(exception.response);
+    response.status(status).json(exception.response ?? exception.message);
   }
 }