ci: run on push/PR, standardize CI workflow

Made-with: Cursor

Author: Jah-yee

.github/workflows/test.yml

@@ -1,6 +1,8 @@
-name: Test (manual only)
+name: CI
 on:
-  workflow_dispatch:
+  push:
+    branches: [main]
+  pull_request:
 jobs:
   test:
     runs-on: ubuntu-latest