freezebase 0.3.0

This release marks the first release of freezebase on PyPI!

Added

• Per-path named AWS profile support in make_s3_upath. Combinable with a custom
  endpoint_url, mutually exclusive with anon=True and explicit
  key/secret/token. Setting a profile takes environment credentials out of
  boto's resolution chain, so the path signs with the profile's keys only.
• aws_session, returning the cached Rasterio AWSSession for an S3 path, and
  clear_aws_session_cache to discard those sessions. Prefer aws_session over
  constructing an AWSSession directly, so every layer signs identically.

Changed

• Renamed the package to freezebase, to allow publication on
  PyPI under the same name. The import path, PyPI distribution name,
  FREEZEBASE_CACHE/FREEZEBASE_DATA environment variables, and the GitHub
  repository all changed accordingly; there is no compatibility shim for the old names.
• s3_env reuses a cached AWSSession per distinct S3 configuration instead of
  building one per call. Constructing a session resolves boto's whole credential
  chain eagerly, and s3_env is entered on every raster operation, so a
  profile-authenticated path previously re-read the shared credentials file
  for every raster read and write. Refreshable STS/SSO credentials still rotate, because
  Rasterio re-freezes them on each Env entry; static credentials rewritten
  mid-process now need clear_aws_session_cache.
• make_s3_upath rejects credentials in client_kwargs, which reach s3fs but
  not s3_env.