feat(sessions): add /resume slash command to open the session browser (#13621)

packages/cli/src/ui/commands/resumeCommand.ts

@@ -0,0 +1,25 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import type {
+  OpenDialogActionReturn,
+  CommandContext,
+  SlashCommand,
+} from './types.js';
+import { CommandKind } from './types.js';
+
+export const resumeCommand: SlashCommand = {
+  name: 'resume',
+  description: 'Browse and resume auto-saved conversations',
+  kind: CommandKind.BUILT_IN,
+  action: async (
+    _context: CommandContext,
+    _args: string,
+  ): Promise<OpenDialogActionReturn> => ({
+    type: 'dialog',
+    dialog: 'sessionBrowser',
+  }),
+};