Add experiment flag to todo list setting (#259891)

* Add experiment flag to todo list setting

* style: update chat todo widget with box-shadow and remove border

Author: bhavyaus

src/vs/workbench/contrib/chat/browser/chat.contribution.ts

@@ -549,7 +549,9 @@ configurationRegistry.registerConfiguration({
 			default: false,
 			description: nls.localize('chat.todoListTool.enabled', "Enables todo lists in chat. This tool allows you to use todo lists in chat."),
 			tags: ['experimental'],
-			included: false,
+			experiment: {
+				mode: 'startup'
+			}
 		},
 		'chat.tools.useTreePicker': {
 			type: 'boolean',

src/vs/workbench/contrib/chat/browser/media/chat.css

@@ -2365,9 +2365,8 @@ display: none;
 	top: 0;
 	z-index: 100;
 	background-color: var(--vscode-sideBar-background);
-	border-bottom: 1px solid var(--vscode-chat-requestBorder);
 	padding: 8px 16px;
-	margin-bottom: 8px;
+	box-shadow: 0 2px 4px var(--vscode-scrollbar-shadow);
 }
 
 .chat-todo-list-widget .todo-list-expand {

src/vs/workbench/contrib/chat/common/tools/manageTodoListTool.ts

@@ -23,7 +23,7 @@ import { ContextKeyExpr } from '../../../../../platform/contextkey/common/contex
 
 export const TodoListToolSettingId = 'chat.todoListTool.enabled';
 
-export const ManageTodoListToolToolId = 'vscode_manageTodoList';
+export const ManageTodoListToolToolId = 'manage_todo_list';
 
 export const ManageTodoListToolData: IToolData = {
 	id: ManageTodoListToolToolId,