fix(desktop): resolve active v2 registry SSH scope

apps/desktop/electron/active-ssh-route.ts

@@ -0,0 +1,19 @@
+import { backendScopeKey, type ConnectionRegistry } from './connection-registry'
+
+/**
+ * Return the live SSH pool scope for the registry connection currently used by
+ * the Sessions workspace. Non-SSH sources deliberately return null so callers
+ * can preserve the legacy v1 routing fallback.
+ */
+export function activeRegistrySshScope(
+  registry: ConnectionRegistry,
+  profile: null | string | undefined
+): null | string {
+  const connection = registry.connections.find(candidate => candidate.id === registry.lastUsed)
+
+  if (!connection || connection.kind !== 'ssh') {
+    return null
+  }
+
+  return backendScopeKey(connection.id, profile)
+}