v3.3.0 — hybrids3 v0.2.0 (presigned PUT URLs)

Adds upload presigning. ?method=PUT (or boto3 put_object) returns a
signed PUT URL; default remains GET. Method is bound into the SigV4
canonical request — GET-signed URLs cannot PUT, vice versa. Public
buckets still require a signed URL for PUT.

See CHANGELOG.md for full details.