Add CI workflow test-on-push

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

Author: a6b8

.github/workflows/test-on-push.yml

@@ -0,0 +1,33 @@
+name: Run Tests on Push
+
+on: push
+
+permissions:
+  contents: read
+  id-token: write
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Use Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run Jest tests (with coverage)
+        run: npm run test:coverage:src
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: ./coverage/lcov.info
+          fail_ci_if_error: false
+          flags: unittests