src/vs/workbench/api/browser/mainThreadNotebookKernels.ts/MainThreadNotebookKernels/$createExecution
class MainThreadNotebookKernels:	$createExecution(handle: number, controllerId: string, rawUri: UriComponents, cellHandle: number): void {
		const uri = URI.revive(rawUri);
		const notebook = this._notebookService.getNotebookTextModel(uri);
		if (!notebook) {
			throw new Error(`Notebook not found: ${uri.toString()}`);
		}

		const kernel = this._notebookKernelService.getMatchingKernel(notebook);
		if (!kernel.selected || kernel.selected.id !== controllerId) {
			throw new Error(`Kernel is not selected: ${kernel.selected?.id} !== ${controllerId}`);
		}
		const execution = this._notebookExecutionStateService.createCellExecution(uri, cellHandle);
		execution.confirm();
		this._executions.set(handle, execution);
	}