Enable auto-deploy on push to main

Previously the Quarto build workflow only ran on manual trigger.
Now it will also run automatically when pushing to main branch.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: rdhyee

.github/workflows/quarto-pages.yml

@@ -1,6 +1,9 @@
 name: Render using Quarto and push to GH-pages
 
-on: workflow_dispatch
+on:
+  push:
+    branches: [main]
+  workflow_dispatch:
 
 jobs:
   build-deploy: