feat: add auto update support

src/main/runtime/update/update-notifications.ts

@@ -0,0 +1,26 @@
+import type { UpdateNotificationType } from '../../../types/config';
+
+export interface UpdateNotificationDeps {
+  showSystemNotification: (title: string, body: string) => void;
+  showOsdNotification: (message: string) => void | Promise<void>;
+  log: (message: string) => void;
+}
+
+export async function notifyUpdateAvailable(
+  options: { notificationType: UpdateNotificationType; version: string },
+  deps: UpdateNotificationDeps,
+): Promise<void> {
+  if (options.notificationType === 'none') return;
+
+  const message = `SubMiner v${options.version} is available`;
+  if (options.notificationType === 'system' || options.notificationType === 'both') {
+    deps.showSystemNotification('SubMiner update available', message);
+  }
+  if (options.notificationType === 'osd' || options.notificationType === 'both') {
+    try {
+      await deps.showOsdNotification(message);
+    } catch (error) {
+      deps.log(`Update OSD notification failed: ${(error as Error).message}`);
+    }
+  }
+}