fix(ci): build collaboration package and trigger on layout-engine changes

Address review feedback:
- Build @superdoc-dev/superdoc-yjs-collaboration in the build job so
  the collaboration/superdoc-yjs smoke test can resolve its dist/
- Add packages/layout-engine/** to path triggers since superdoc
  bundles it and regressions there should run example tests

Author: caio-pizzol

.github/workflows/ci-examples.yml

@@ -9,6 +9,7 @@ on:
       - 'packages/super-editor/**'
       - 'packages/collaboration-yjs/**'
       - 'packages/sdk/**'
+      - 'packages/layout-engine/**'
       - 'shared/**'
   workflow_dispatch:
 
@@ -35,6 +36,9 @@ jobs:
       - name: Build React wrapper
         run: pnpm --filter @superdoc-dev/react build
 
+      - name: Build collaboration package
+        run: pnpm --filter @superdoc-dev/superdoc-yjs-collaboration build
+
       - name: Install Playwright
         working-directory: examples/__tests__
         run: npx playwright install chromium