Add CI workflow for PRs and main pushes

.forgejo/workflows/ci.yml

@@ -0,0 +1,25 @@
+# CI: run the test suite on every pull request and on pushes to main, so
+# regressions are caught before they reach a release tag.
+#
+# Requirements:
+#   - A Forgejo Actions runner on the instance. Adjust `runs-on` to a label
+#     your runner actually advertises (common: docker, ubuntu-latest).
+
+name: ci
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  test:
+    runs-on: docker
+    container:
+      image: node:22-bookworm
+    steps:
+      - name: Check out commit
+        uses: actions/checkout@v4
+
+      - name: Run tests
+        run: npm ci && npm test