workflow: run tests and builds for pull requests

.github/workflows/ci.yml

@@ -4,6 +4,9 @@ on:
   push:
     branches:
       - main
+  pull_request:
+    branches:
+      - main
   workflow_dispatch:
 
 jobs:
@@ -100,6 +103,8 @@ jobs:
       - test
       - build-web
 
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+
     permissions:
       pages: write
       id-token: write