Implement start of terminal renderers

Part of #46192

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -425,6 +425,9 @@ export function createApiFactory(
 				}
 				return extHostTerminalService.createTerminal(<string>nameOrOptions, shellPath, shellArgs);
 			},
+			createTerminalRenderer(name: string): vscode.TerminalRenderer {
+				return extHostTerminalService.createTerminalRenderer(name);
+			},
 			registerTreeDataProvider(viewId: string, treeDataProvider: vscode.TreeDataProvider<any>): vscode.Disposable {
 				return extHostTreeViews.registerTreeDataProvider(viewId, treeDataProvider);
 			},