Add Icechunk #140

@jhamman Please have a member of the Icechunk team complete the missing items from the checklist to get started. (There are none left though given my reading of earth-mover/icechunk#1204 (comment))

• Create an account on Anaconda Cloud
• Reply here with the link to your account (https://anaconda.org/jhamman)
• Make a new Anaconda Cloud API token with permissions described in https://scientific-python.org/specs/spec-0004/#process-for-adding-new-projects

• Save the API token as a repo GitHub Actions secret named ANACONDA_ORG_UPLOAD_TOKEN
• Direct @scientific-python/nightly-wheels-developers to a icechunk nightly wheel for us to upload to create the package in the registry
• Verify that we have added you to the icechunk team "Group" on https://anaconda.org/scientific-python-nightly-wheels
• Verify that we have added the package scientific-python-nightly-wheels/icechunk to the icechunk team "Group"

If you'd also like to use the scientific/upload-nightly-action GitHub Action please check out the action repo's README. If you need to collect wheels from different CI jobs, consider creating a new GitHub Actions workflow with logic similar to matplotlib's or Awkward's.

If you have any questions please just ask here!