split vscode.proposed.d.ts into a file per proposal, https://github.com/microsoft/vscode/issues/131165

src/vscode-dts/vscode.proposed.notebookCellExecutionState.d.ts

@@ -0,0 +1,52 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+declare module 'vscode' {
+
+	// https://github.com/microsoft/vscode/issues/124970
+
+	/**
+	 * The execution state of a notebook cell.
+	 */
+	export enum NotebookCellExecutionState {
+		/**
+		 * The cell is idle.
+		 */
+		Idle = 1,
+		/**
+		 * Execution for the cell is pending.
+		 */
+		Pending = 2,
+		/**
+		 * The cell is currently executing.
+		 */
+		Executing = 3,
+	}
+
+	/**
+	 * An event describing a cell execution state change.
+	 */
+	export interface NotebookCellExecutionStateChangeEvent {
+		/**
+		 * The {@link NotebookCell cell} for which the execution state has changed.
+		 */
+		readonly cell: NotebookCell;
+
+		/**
+		 * The new execution state of the cell.
+		 */
+		readonly state: NotebookCellExecutionState;
+	}
+
+	export namespace notebooks {
+
+		/**
+		 * An {@link Event} which fires when the execution state of a cell has changed.
+		 */
+		// todo@API this is an event that is fired for a property that cells don't have and that makes me wonder
+		// how a correct consumer works, e.g the consumer could have been late and missed an event?
+		export const onDidChangeNotebookCellExecutionState: Event<NotebookCellExecutionStateChangeEvent>;
+	}
+}