perf(zarr-transforms): partition sorted 1-D array maps by chunk

[selmanozleyen]

See the conversation here: zarr-developers#4170 (comment)

Regression check:

case                    #3906 head   proposed   proposed/head
random, one shard          18.136      18.175       1.0053
descending, one shard      18.352      18.176       0.9898
random, all shards        274.906     275.353       0.9985

The speedup for this case:

runs    elements    transform build    proposed resolution
1024      1.48M          0.74 ms              2.28 ms
4096      5.94M          5.03 ms              9.24 ms
8192     11.9M           9.72 ms             18.00 ms