fix: add missing mock for onDidChangeActiveTextEditor in tests

Author: NaccOll

src/core/webview/__tests__/ClineProvider.sticky-mode.spec.ts

@@ -27,6 +27,7 @@ vi.mock("vscode", () => ({
 		showInformationMessage: vi.fn(),
 		showWarningMessage: vi.fn(),
 		showErrorMessage: vi.fn(),
+		onDidChangeActiveTextEditor: vi.fn(() => ({ dispose: vi.fn() })),
 	},
 	workspace: {
 		getConfiguration: vi.fn().mockReturnValue({