- Move worker.py -> execution/worker.py, executor.py -> execution/executor.py (byte-identical copies; import sites updated) - Merge old execution.py + notebook_runner.py into execution/runners/notebook.py: subprocess CLI (main/emit_outputs) plus the in-process helpers (_execute_notebook/_execute_python/execute_artifact) - schedule/notebook_runner.py becomes a compatibility shim so `python -m schedule.notebook_runner` (the worker's stable -m string) still works - Delete flat execution.py (shadowed by the new execution/ package) - Zero behavior change; schedule/pyproject.toml untouched Co-Authored-By: Claude <noreply@anthropic.com>