feat(cordn): 'Open in Staircase' link on the crew coordinator card

CrewCoordinatorCard now offers a StaircaseLink in both branches: our coordinator (SKATESPOTS_COORDINATOR add-link) when a crew has none, and the crew's own coordinator add-link when it has a pubkey (falls back to the Cordn home otherwise). Lets crews jump to real MLS chat in the native Cordn client.

AGENTS.md

@@ -2134,7 +2134,10 @@ The community relay moved off the hosted relay.tools instance
   default; **Settings → Coordinator** shows a "Use SkateSpots coordinator" block
   and **CrewForm** prefills it for new crews. Disclosure copy lives in
   `socialUi.coordinator.ourDefault*` + the existing `privacyNote` (coordinators see
-  ciphertext + metadata, never contents).
+  ciphertext + metadata, never contents). `CrewCoordinatorCard` shows an **"Open in
+  Staircase"** link (`coordinatorAddUrl`) in both branches (the native Cordn client
+  for real MLS) — our coordinator by default, a BYO coordinator's add-link when it
+  has a pubkey.
 - **Cutover (2026-10-12):** `SKATE_RELAY` (`src/lib/types.ts`) → the new relay; the
   default pools, the DM/CVM/zap relay arrays, the `cvm-server` + `push-service`
   defaults, and the archive default all point at the new relay.

src/components/crew/CrewCoordinatorCard.tsx

@@ -7,7 +7,7 @@ import { useTranslation } from '@/contexts/language';
 import { genUserName } from '@/lib/genUserName';
 import { sanitizeUrl, urlDomain } from '@/lib/sanitizeUrl';
 import { resolveCordnEndpoint } from '@/lib/cordn/endpoint';
-import { CORDN_RELAY_URL } from '@/lib/coordinator';
+import { CORDN_RELAY_URL, coordinatorAddUrl, CORDN_HOME, SKATESPOTS_COORDINATOR } from '@/lib/coordinator';
 import type { CrewCoordinator, SkateCrew } from '@/lib/types';
 import { nip19 } from 'nostr-tools';
 
@@ -61,6 +61,7 @@ export function CrewCoordinatorCard({
             <span className="font-semibold text-gray-200">{t('socialUi.crewCoordinator.chatWord')}</span> {t('socialUi.crewCoordinator.defaultB')}{' '}
             <span className="font-bold text-teal-300">{t('socialUi.crewCoordinator.e2ee')}</span> {t('socialUi.crewCoordinator.defaultC')}
           </p>
+          <StaircaseLink coordinator={SKATESPOTS_COORDINATOR} />
           {isFounder && (
             <p className="text-[11px] leading-relaxed text-gray-600">
               {t('socialUi.crewCoordinator.advancedA')}{' '}
@@ -101,6 +102,13 @@ export function CrewCoordinatorCard({
 
         {coordinator.operator && <CoordinatorOperator pubkey={coordinator.operator} />}
 
+        <StaircaseLink
+          coordinator={{
+            pubkey: coordinator.pubkey,
+            relays: /^wss?:\/\//i.test(coordinator.url) ? [coordinator.url] : [],
+          }}
+        />
+
         {endpoint && (
           <p className="text-[11px] leading-relaxed text-gray-500">
             {t('socialUi.crewCoordinator.deliveredOver')}{' '}
@@ -135,6 +143,25 @@ export function CrewCoordinatorCard({
   );
 }
 
+/** Link to open a coordinator in Staircase (the native Cordn client) for real
+ * MLS chat. Falls back to the Cordn home when the coordinator has no pubkey. */
+function StaircaseLink({ coordinator }: { coordinator: { pubkey?: string; relays?: string[] } }) {
+  const { t } = useTranslation();
+  const href = coordinator.pubkey
+    ? coordinatorAddUrl({ pubkey: coordinator.pubkey, relays: coordinator.relays ?? [] })
+    : CORDN_HOME;
+  return (
+    <a
+      href={href}
+      target="_blank"
+      rel="noopener noreferrer"
+      className="inline-flex items-center gap-1.5 rounded-lg border border-teal-500/30 bg-teal-500/10 px-2.5 py-1.5 text-xs font-bold text-teal-300 transition-colors hover:bg-teal-500/20"
+    >
+      <ExternalLink className="h-3.5 w-3.5" /> {t('socialUi.crewCoordinator.openInStaircase')}
+    </a>
+  );
+}
+
 function CoordinatorEndpoint({ coordinator }: { coordinator: CrewCoordinator }) {
   const { t } = useTranslation();
   const safe = sanitizeUrl(coordinator.url);

src/i18n/en.ts

@@ -4045,6 +4045,7 @@ socialUi: {
       ownRelaySafe: "Nothing crew-specific leaves your crew's own relay.",
       manage: 'Manage coordinator',
       open: 'Open {{domain}}',
+      openInStaircase: 'Open in Staircase',
       runBy: 'Coordinator run by',
     },
     dms: {

src/i18n/es.ts

@@ -4045,6 +4045,7 @@ socialUi: {
       ownRelaySafe: 'Nada específico de la peña sale del relé propio de tu peña.',
       manage: 'Gestionar coordinador',
       open: 'Abrir {{domain}}',
+      openInStaircase: 'Abrir en Staircase',
       runBy: 'Coordinador gestionado por',
     },
     dms: {