ci: install nodejs before checkout

actions/checkout@v4 is a JavaScript action and the archlinux image ships no
node, so it failed with `exec: "node": executable file not found in $PATH`.
A `run:` step does not require a checkout, so the toolchain is installed
first and the standard action then works unchanged.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.gitea/workflows/update.yaml

@@ -53,12 +53,16 @@ jobs:
           - tsparams
 
     steps:
-      - uses: actions/checkout@v4
-
-      - name: Install dependencies
+      # Must come BEFORE actions/checkout. That action is JavaScript, and the
+      # archlinux image ships no node, so checkout dies with
+      # `exec: "node": executable file not found in $PATH`. A `run:` step needs
+      # no checkout, so the toolchain can be installed first.
+      - name: Bootstrap container
         run: |
           pacman -Syu --noconfirm --needed \
-            git openssh jq curl pacman-contrib namcap fuse2 python
+            nodejs git openssh jq curl pacman-contrib namcap fuse2 python
+
+      - uses: actions/checkout@v4
 
       - name: Configure git and SSH
         env: