refactor(ops): standardize image-based production delivery

.github/workflows/release-image.yml

@@ -1,6 +1,8 @@
 name: Release Image
 
 on:
+  push:
+    branches: [main]
   workflow_dispatch:
     inputs:
       image_tag:
@@ -61,3 +63,12 @@ jobs:
           tags: ${{ steps.vars.outputs.migrator_image }}
           cache-from: type=gha,scope=migrator-image
           cache-to: type=gha,mode=max,scope=migrator-image
+
+      - name: Publish release summary
+        run: |
+          {
+            echo "## Image release"
+            echo
+            echo "- App image: \`${{ steps.vars.outputs.app_image }}\`"
+            echo "- Migrator image: \`${{ steps.vars.outputs.migrator_image }}\`"
+          } >> "$GITHUB_STEP_SUMMARY"