The collection of connectivity algorithms had a couple of inefficiencies.
By moving to using WorkId we can remove a couple of arrays of the same size
as the input domain. In addition by moving to using atomics we can remove
an bool output array with a size equivalent to the input domain and
a call to reduce.
The previous algorithm terminates based on if all pixels are in a root star. It turns out to be in
sufficient and thus terminates much earlier than it is required.
ImageConnectivity worklet implements a parallel connected component
labeling algorithm for 2D structured grids/images. For each pixel,
it search for the pixel's 6 neighbors and classify them as the
same connected component if their corresponding "color" field have
the same value.
