Apply suggestions from code review

Author: jhamman

src/zarr/core/indexing.py

@@ -848,6 +848,7 @@ def __iter__(self) -> Iterator[ChunkProjection]:
 class OIndex:
     array: Array
 
+    # TODO: develop Array generic and move zarr.Array[np.intp] | zarr.Array[np.bool_] to ArrayOfIntOrBool
     def __getitem__(self, selection: OrthogonalSelection | Array) -> NDArrayLike:
         from zarr.core.array import Array
 
@@ -1142,6 +1143,7 @@ def __init__(self, selection: MaskSelection, shape: ChunkCoords, chunk_grid: Chu
 class VIndex:
     array: Array
 
+    # TODO: develop Array generic and move zarr.Array[np.intp] | zarr.Array[np.bool_] to ArrayOfIntOrBool
     def __getitem__(self, selection: CoordinateSelection | MaskSelection | Array) -> NDArrayLike:
         from zarr.core.array import Array