docs(toc): add Bundles and Authentication to the Reference nav (#3267)

docs/reference/bundles.md and docs/reference/authentication.md exist on
disk but were absent from the Reference section of docs/toc.yml, so both
pages were orphaned and undiscoverable in the published docs sidebar.
Add the two nav entries (Bundles after Workflows, matching the ordering
in reference/overview.md; Authentication last).

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

docs/toc.yml

@@ -35,6 +35,10 @@
       href: reference/presets.md
     - name: Workflows
       href: reference/workflows.md
+    - name: Bundles
+      href: reference/bundles.md
+    - name: Authentication
+      href: reference/authentication.md
 
 # Concepts
 - name: Concepts