CI: the runner image has no iproute2; the bastion smoke start needs ip route

With stderr finally surfaced, the last failing test says it plainly:
detectInterface() shells out to `ip route` and the image does not ship it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V6HNx6cyr4J4CiMGCy1wkF

.gitea/workflows/ci.yml

@@ -85,10 +85,10 @@ jobs:
       - name: Generate Prisma client (labd typecheck needs it)
         run: pnpm -C src/labd run db:generate
 
-      - name: Install test validators (ubuntu-autoinstall parses YAML via python, kickstart.test runs ksvalidator)
+      - name: Install test validators (ubuntu-autoinstall parses YAML via python, kickstart.test runs ksvalidator, the bastion smoke start runs `ip route`)
         # pykickstart is not in the runner image's apt sources -- pip it is.
         run: |
-          sudo apt-get update -qq && sudo apt-get install -y -qq python3-yaml python3-pip
+          sudo apt-get update -qq && sudo apt-get install -y -qq python3-yaml python3-pip iproute2
           sudo pip3 install --quiet --break-system-packages pykickstart
 
       - name: Build (needed by completions check)