- Fixed edge cases in `compute_face_normal` to use stable edge definition for quad faces (corners[1]-corners[0] x corners[3]-corners[0]).
- Fixed edge cases in compute_face_normal to use stable edge definition for quad faces (corners[1]-corners[0] x corners[3]-corners[0]).
- Added explicit shape validation and zero-norm guards in rotation_align_vectors.
- Ensured concrete np.ndarray return types with explicit astype(np.float64) to satisfy type checking.

## Type Checking Warnings
- `basedpyright` reports numerous warnings, mostly related to `Any` types from `cv2` and `pyzed.sl` bindings which lack full type stubs.
- Deprecation warnings for `List`, `Dict`, `Tuple` (Python 3.9+) are present but existing style uses them. Kept consistent with existing code.
- `reportUnknownVariableType` is common due to dynamic nature of OpenCV/ZED returns.

## Parquet Metadata Handling
- `awkward` library used for parquet reading returns jagged arrays for list columns like `ids`.
- `ak.to_list()` is necessary to convert these to standard Python lists for dictionary values.

## Backward Compatibility
- While `FACE_MARKER_MAP` constant remains in `aruco/alignment.py` for potential external consumers, it is no longer used by the CLI tool.
- Users with old parquet files will now see a warning and no alignment, rather than silent fallback to potentially incorrect hardcoded IDs.



- None encountered during test implementation. API signatures were consistent with the implementation in `aruco/alignment.py`.


## Runtime Errors

## Messaging Consistency

## Iteration Speed

## Test Collection Noise

## Debugging Heuristics

## Documentation Gaps
- Users were unclear on how `--auto-align` made decisions (heuristic vs explicit) and what `--refine-depth` actually did. The new documentation addresses this by explaining the decision flow and the optimization objective function.