Trigger container build on push to main

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

Author: shanemcd

.github/workflows/build-images.yml

@@ -1,6 +1,9 @@
 name: Build Container Images
 
 on:
+  push:
+    branches:
+      - main
   workflow_dispatch:
   schedule:
     # Run nightly at 2:00 AM Eastern (7:00 AM UTC)