# IMPLEMENTATION: move-completed-tasks-to-complete-folder

## Summary

When `--transition complete` is called, the task directory is now moved from `tasks/<name>/` to `tasks/complete/<name>/`. The `_task_dir` function has a fallback to find completed tasks. `--list` and `--audit` exclude completed tasks.

## Changes

### R1 -- `_task_dir` fallback (scripts/status.py:236-249)

Added a fallback check: if `tasks/<name>/` doesn't exist, check `tasks/complete/<name>/`. This ensures `--task <name>`, `--transition`, `--approve`, and all other commands that call `_task_dir` still find completed tasks.

### R2 -- `cmd_transition` moves task directory (scripts/status.py:601-610)

After `_write_state(task_path, target)`, if `target == "complete"`, the function:
1. Computes the tasks root directory (`task_path.parent`)
2. Creates `tasks/complete/` if it doesn't exist
3. Renames `task_path` to `tasks/complete/<name>/`
4. Refuses if a completed task with the same name already exists

### R3 -- `_all_task_dirs` unchanged

`_all_task_dirs` does NOT scan `tasks/complete/`. Only `--task <name>` with fallback can find completed tasks.

### R4 -- Tests

`tests/test_move_completed.py`: 9 tests across 3 classes:
- `TestTaskDirFallback` (3 tests): regular path, completed fallback, regular preference
- `TestAllTaskDirsExcludesCompleted` (1 test): completed tasks excluded from listing
- `TestCompleteMovesDir` (5 tests): move, dir creation, create-task refusal, transition refusal, state read after move

### R5 -- Documentation

- `CHANGELOG.md`: task 9 entry

## Verification

- `python3 -m py_compile scripts/status.py` -- OK
- `python3 -m pytest tests/test_move_completed.py -v` -- 9 passed
- `python3 -m pytest tests/ -q` -- 433 passed (424 + 9 new)