Add iOS node push-token registration foundation

src/gateway/handlers/system.ts

@@ -2,7 +2,7 @@ import type { GatewayRequest, OutboundMessage } from '../protocol.js';
 import { makeResponse, makeError, ErrorCode } from '../protocol.js';
 import type { MetricsSnapshot, EventEntry, ActiveRequestInfo } from '../metrics.js';
 import type { ServiceInfo } from './services.js';
-import type { NodeLocation, NodeStatus } from './node.js';
+import type { NodeLocation, NodeStatus, NodePushToken } from './node.js';
 
 /** Per-session token usage report returned by system.tokenUsage. */
 export interface TokenUsageEntry {
@@ -39,6 +39,15 @@ export interface NodeEntry {
   registeredAt: number;
   location?: NodeLocation;
   status?: NodeStatus;
+  push?: NodePushTokenSummary;
+}
+
+export interface NodePushTokenSummary {
+  provider: NodePushToken['provider'];
+  tokenPreview: string;
+  topic?: string;
+  environment: NodePushToken['environment'];
+  registeredAt: number;
 }
 
 export interface SystemHandlerDeps {