Add canvas artifact RPC foundation for A2UI

src/gateway/server.ts

@@ -7,6 +7,7 @@ import { SessionBridge } from './session-bridge.js';
 import type { SessionBridgeConfig } from './session-bridge.js';
 import { LaneQueue } from './lane-queue.js';
 import type { LaneQueueConfig } from './lane-queue.js';
+import { CanvasStore } from './canvas-store.js';
 import { MetricsCollector } from './metrics.js';
 import { authenticateRequest, authorizeNodeMethod } from './auth.js';
 import type { AuthConfig } from './auth.js';
@@ -28,6 +29,7 @@ import {
   createIntentHandlers,
   createRoutingHandlers,
   createHistoryHandlers,
+  createCanvasHandlers,
   createNodeHandlers,
 } from './handlers/index.js';
 import { discoverServices } from './handlers/services.js';
@@ -133,6 +135,7 @@ export class GatewayServer {
   private router: Router;
   private sessionBridge: SessionBridge;
   private laneQueue: LaneQueue;
+  private canvasStore: CanvasStore;
   private metrics: MetricsCollector;
   private discoveryHandle: GatewayDiscoveryHandle | null = null;
   private connectionMap: Map<WebSocket, string> = new Map();
@@ -160,6 +163,7 @@ export class GatewayServer {
     });
 
     this.laneQueue = new LaneQueue(config.queue);
+    this.canvasStore = new CanvasStore();
     this.metrics = new MetricsCollector({
       getQueueDepth: () => this.laneQueue.totalPending(),
     });
@@ -235,6 +239,10 @@ export class GatewayServer {
       sessionManager: this.config.sessionManager,
     });
 
+    const canvasHandlers = createCanvasHandlers({
+      store: this.canvasStore,
+    });
+
     const toolHandlers = createToolHandlers({
       toolRegistry: this.config.toolRegistry,
       toolExecutor: this.config.toolExecutor,
@@ -365,6 +373,9 @@ export class GatewayServer {
     for (const [method, handler] of Object.entries(historyHandlers)) {
       this.router.register(method, handler);
     }
+    for (const [method, handler] of Object.entries(canvasHandlers)) {
+      this.router.register(method, handler);
+    }
     for (const [method, handler] of Object.entries(toolHandlers)) {
       this.router.register(method, handler);
     }