Upgrade Pcodec to v1 #815
Description
We recently released Pcodec v1 with a lot of new improvements, a new format version, and some small API tweaks: https://github.com/pcodec/pcodec/releases/tag/v1.0.0
Naturally, v1 will still be able to decode all previously encoded pco data, but the reverse is not always true. If this is within numcodecs's contract, it makes the most sense to upgrade directly; otherwise we should think about how to do this.