fix self ai plan generation authorization and error handling

apps/mobile/src/api/recommendations.ts

@@ -124,10 +124,20 @@ export async function generateSelfRecommendation(
     );
     return parseApiData<Recommendation>(response.data);
   } catch (error) {
-    if (isAxiosError(error) && error.response) {
-      throw new Error(
-        `Failed to generate recommendation: ${error.response.status}`,
-      );
+    if (isAxiosError(error)) {
+      const responseError = error.response?.data as
+        | { error?: string }
+        | undefined;
+
+      if (responseError?.error) {
+        throw new Error(responseError.error);
+      }
+
+      if (error.response) {
+        throw new Error(
+          `Failed to generate recommendation: ${error.response.status}`,
+        );
+      }
     }
     throw error;
   }