docs: add vin-decoder to pre-launch checklist quick-command snippets

Fix three omissions in the Quick Commands Reference section:
1. Pod-health loop: add vin-decoder to namespace list
2. DNS check loop: add vin subdomain (8th subdomain, not 7)
3. Health smoke-test loop: add vin.leeworks.dev/v1/health

Closes leeworks-agents/api-company#208

docs/pre-launch-checklist.md

@@ -77,7 +77,7 @@ Use this checklist as the final go-live gate — run through every item the day
 flux get all
 
 # Check API pod health
-for ns in zip-enrichment holidays air-quality docs-site; do
+for ns in zip-enrichment holidays air-quality vin-decoder docs-site; do
   echo "=== $ns ==="
   kubectl get pods -n $ns
 done
@@ -85,13 +85,13 @@ done
 # Verify TLS certs
 kubectl get certificates -A
 
-# Check all 7 DNS subdomains
-for sub in zip holidays aqi docs status registry grafana; do
+# Check all 8 DNS subdomains
+for sub in zip holidays aqi vin docs status registry grafana; do
   echo "$sub.leeworks.dev -> $(dig $sub.leeworks.dev +short)"
 done
 
 # Smoke test health endpoints
-for svc in "zip.leeworks.dev/health" "holidays.leeworks.dev/health" "aqi.leeworks.dev/health"; do
+for svc in "zip.leeworks.dev/health" "holidays.leeworks.dev/health" "aqi.leeworks.dev/health" "vin.leeworks.dev/v1/health"; do
   echo "$svc: $(curl -s -o /dev/null -w '%{http_code}' https://$svc)"
 done