feat(coding-agent): add hidden thinking label api closes #2673

packages/coding-agent/src/core/extensions/runner.ts

@@ -178,6 +178,7 @@ const noOpUIContext: ExtensionUIContext = {
 	onTerminalInput: () => () => {},
 	setStatus: () => {},
 	setWorkingMessage: () => {},
+	setHiddenThinkingLabel: () => {},
 	setWidget: () => {},
 	setFooter: () => {},
 	setHeader: () => {},

packages/coding-agent/src/core/extensions/types.ts

@@ -127,6 +127,9 @@ export interface ExtensionUIContext {
 	/** Set the working/loading message shown during streaming. Call with no argument to restore default. */
 	setWorkingMessage(message?: string): void;
 
+	/** Set the label shown for hidden thinking blocks. Call with no argument to restore default. */
+	setHiddenThinkingLabel(label?: string): void;
+
 	/** Set a widget to display above or below the editor. Accepts string array or component factory. */
 	setWidget(key: string, content: string[] | undefined, options?: ExtensionWidgetOptions): void;
 	setWidget(