Install Node.js before Checkout in the CI/CD workflow

Host-mode jobs execute directly on the bare runner container rather
than a per-job container, and actions/checkout is a JS action — it
needs `node` on PATH to run at all, which the runner image doesn't
ship. Failed every run with "Cannot find: node in PATH" before any
other step got a chance to install anything.

.gitea/workflows/ci-cd.yml

@@ -17,6 +17,15 @@ jobs:
   build-test-deploy:
     runs-on: host
     steps:
+      # `runs-on: host` runs every step directly on the bare runner
+      # container instead of spinning up a fresh container per job, and
+      # `actions/checkout` below is a JS action — it needs a `node` binary
+      # on PATH to run at all, which this image doesn't ship. Has to come
+      # before Checkout, since Checkout itself is what fails without it.
+      - name: Install Node.js
+        shell: bash
+        run: apk add --no-cache nodejs
+
       - name: Checkout
         uses: https://github.com/actions/checkout@v4