fix(llmo-config): polish LlmoConfigValidationError per review

Address minor polish items from PR #1574 review:

- Pass { cause: zodError } to super() so the original ZodError stack is
  preserved on the cause chain. Improves debuggability without changing
  the public error shape.
- Use issue `code` instead of `message` in the summary string. Zod's
  default messages can echo received values, and the LLMO config can
  carry user-curated content (brand names, competitor URLs) on the
  api-service write path. The full human-readable detail (including the
  values) remains on `this.issues` for trusted callers to inspect.
- Lock down the message-format contract with a regex assertion so the
  path-shape (e.g. categories.<uuid>.region) is not silently dropped by
  a future maintainer.
- Switch the test fixture UUID to a v4-conformant value so Zod's
  validation reaches the inner field rather than failing at the record
  key.

Refs: SITES-43238

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: dzehnder

packages/spacecat-shared-utils/src/llmo-config.js

@@ -26,10 +26,17 @@ import { llmoConfig } from './schemas.js';
  */
 export class LlmoConfigValidationError extends Error {
   constructor(siteId, zodError) {
+    // Use issue `code` rather than `message` in the summary: Zod's default
+    // messages can echo received values, which may include user-supplied
+    // content (brand names, competitor URLs) on the api-service write path.
+    // The full message and value remain on `this.issues` for trusted callers.
     const summary = zodError.issues
-      .map((i) => `${i.path.join('.')}: ${i.message}`)
+      .map((i) => `${i.path.join('.')}: ${i.code}`)
       .join('; ');
-    super(`LLMO config for site ${siteId} failed schema validation: ${summary}`);
+    super(
+      `LLMO config for site ${siteId} failed schema validation: ${summary}`,
+      { cause: zodError },
+    );
     this.name = 'LlmoConfigValidationError';
     this.siteId = siteId;
     this.issues = zodError.issues;

packages/spacecat-shared-utils/test/llmo-config.test.js

@@ -206,7 +206,7 @@ describe('llmo-config utilities', () => {
       const invalidConfig = {
         ...validConfig,
         categories: {
-          '00000000-0000-0000-0000-000000000001': { name: 'brand', region: 'en-us' },
+          '550e8400-e29b-41d4-a716-446655440000': { name: 'brand', region: 'en-us' },
         },
       };
 
@@ -224,11 +224,11 @@ describe('llmo-config utilities', () => {
       expect(s3Client.send).not.called;
     });
 
-    it('LlmoConfigValidationError carries siteId, name, and Zod issues', async () => {
+    it('LlmoConfigValidationError carries siteId, name, Zod issues, and cause', async () => {
       const invalidConfig = {
         ...validConfig,
         categories: {
-          '00000000-0000-0000-0000-000000000001': { name: 'brand', region: 'en-us' },
+          '550e8400-e29b-41d4-a716-446655440000': { name: 'brand', region: 'en-us' },
         },
       };
 
@@ -243,7 +243,14 @@ describe('llmo-config utilities', () => {
       expect(caught.name).equals('LlmoConfigValidationError');
       expect(caught.siteId).equals(siteId);
       expect(caught.issues).to.be.an('array').with.length.greaterThan(0);
+
+      // Message format: "...failed schema validation: <path>: <code>"
       expect(caught.message).to.include(siteId);
+      expect(caught.message).to.match(/categories\..+\.region/);
+
+      // Original ZodError preserved as cause for stack-chain debugging.
+      expect(caught.cause).to.exist;
+      expect(caught.cause.issues).to.equal(caught.issues);
     });
   });