fix: preserve service ID on subdomain change, accept localhost as IP

- serviceUrl() now checks service.url before falling back to buildServiceUrl(id)
- Service update no longer overwrites ID with the new subdomain
- Accept "localhost" as valid IP in service update validation
- Find services by ID or URL match when updating

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

status/js/core/grid.js

@@ -77,7 +77,14 @@
     }
   }
 
-  function serviceUrl(id) { return buildServiceUrl(id); }
+  function serviceUrl(id) {
+    const svc = window.APPS?.find(a => a.id === id);
+    if (svc?.url) return svc.url.startsWith('http') ? svc.url : 'https://' + svc.url;
+    if (svc?.isExternal && svc.externalUrl) return svc.externalUrl;
+    const dns = SITE.dnsServers?.[id];
+    if (dns) return 'http://' + dns.ip + ':' + (dns.port || 5380);
+    return buildServiceUrl(id);
+  }
   function el(tag, cls, txt) { const n = document.createElement(tag); if (cls) n.className = cls; if (txt) n.textContent = txt; return n; }
 
   function buildGrid() {