refactor: unify restart gating and update availability sync

src/gateway/events.ts

@@ -0,0 +1,7 @@
+import type { UpdateAvailable } from "../infra/update-startup.js";
+
+export const GATEWAY_EVENT_UPDATE_AVAILABLE = "update.available" as const;
+
+export type GatewayUpdateAvailableEventPayload = {
+  updateAvailable: UpdateAvailable | null;
+};

src/gateway/server-methods-list.ts

@@ -1,4 +1,5 @@
 import { listChannelPlugins } from "../channels/plugins/index.js";
+import { GATEWAY_EVENT_UPDATE_AVAILABLE } from "./events.js";
 
 const BASE_METHODS = [
   "health",
@@ -117,4 +118,5 @@ export const GATEWAY_EVENTS = [
   "voicewake.changed",
   "exec.approval.requested",
   "exec.approval.resolved",
+  GATEWAY_EVENT_UPDATE_AVAILABLE,
 ];

src/gateway/server-reload-handlers.ts

@@ -2,6 +2,7 @@ import { getActiveEmbeddedRunCount } from "../agents/pi-embedded-runner/runs.js"
 import { getTotalPendingReplies } from "../auto-reply/reply/dispatcher-registry.js";
 import type { CliDeps } from "../cli/deps.js";
 import { resolveAgentMaxConcurrent, resolveSubagentMaxConcurrent } from "../config/agent-limits.js";
+import { isRestartEnabled } from "../config/commands.js";
 import type { loadConfig } from "../config/config.js";
 import { startGmailWatcherWithLogs } from "../hooks/gmail-watcher-lifecycle.js";
 import { stopGmailWatcher } from "../hooks/gmail-watcher.js";
@@ -48,7 +49,7 @@ export function createGatewayReloadHandlers(params: {
     plan: GatewayReloadPlan,
     nextConfig: ReturnType<typeof loadConfig>,
   ) => {
-    setGatewaySigusr1RestartPolicy({ allowExternal: nextConfig.commands?.restart === true });
+    setGatewaySigusr1RestartPolicy({ allowExternal: isRestartEnabled(nextConfig) });
     const state = params.getState();
     const nextState = { ...state };
 
@@ -138,7 +139,7 @@ export function createGatewayReloadHandlers(params: {
     plan: GatewayReloadPlan,
     nextConfig: ReturnType<typeof loadConfig>,
   ) => {
-    setGatewaySigusr1RestartPolicy({ allowExternal: nextConfig.commands?.restart === true });
+    setGatewaySigusr1RestartPolicy({ allowExternal: isRestartEnabled(nextConfig) });
     const reasons = plan.restartReasons.length
       ? plan.restartReasons.join(", ")
       : plan.changedPaths.join(", ");

src/gateway/server.impl.ts

@@ -8,6 +8,7 @@ import type { CanvasHostServer } from "../canvas-host/server.js";
 import { type ChannelId, listChannelPlugins } from "../channels/plugins/index.js";
 import { formatCliCommand } from "../cli/command-format.js";
 import { createDefaultDeps } from "../cli/deps.js";
+import { isRestartEnabled } from "../config/commands.js";
 import {
   CONFIG_PATH,
   isNixMode,
@@ -49,6 +50,10 @@ import { createAuthRateLimiter, type AuthRateLimiter } from "./auth-rate-limit.j
 import { startChannelHealthMonitor } from "./channel-health-monitor.js";
 import { startGatewayConfigReloader } from "./config-reload.js";
 import type { ControlUiRootState } from "./control-ui.js";
+import {
+  GATEWAY_EVENT_UPDATE_AVAILABLE,
+  type GatewayUpdateAvailableEventPayload,
+} from "./events.js";
 import { ExecApprovalManager } from "./exec-approval-manager.js";
 import { NodeRegistry } from "./node-registry.js";
 import type { startBrowserControlServerIfEnabled } from "./server-browser.js";
@@ -252,7 +257,7 @@ export async function startGatewayServer(
   if (diagnosticsEnabled) {
     startDiagnosticHeartbeat();
   }
-  setGatewaySigusr1RestartPolicy({ allowExternal: cfgAtStart.commands?.restart === true });
+  setGatewaySigusr1RestartPolicy({ allowExternal: isRestartEnabled(cfgAtStart) });
   setPreRestartDeferralCheck(
     () => getTotalQueueSize() + getTotalPendingReplies() + getActiveEmbeddedRunCount(),
   );
@@ -628,7 +633,15 @@ export async function startGatewayServer(
     isNixMode,
   });
   if (!minimalTestGateway) {
-    scheduleGatewayUpdateCheck({ cfg: cfgAtStart, log, isNixMode });
+    scheduleGatewayUpdateCheck({
+      cfg: cfgAtStart,
+      log,
+      isNixMode,
+      onUpdateAvailableChange: (updateAvailable) => {
+        const payload: GatewayUpdateAvailableEventPayload = { updateAvailable };
+        broadcast(GATEWAY_EVENT_UPDATE_AVAILABLE, payload, { dropIfSlow: true });
+      },
+    });
   }
   const tailscaleCleanup = minimalTestGateway
     ? null