A BlobStore backed by any object_store::ObjectStore — S3, GCS, Azure,
or the in-memory / local stores object_store ships. Construct it with one of
the provider builders below, or from_object_store for full control.
Azure Blob Storage, credentials from the standard environment
(AZURE_STORAGE_ACCOUNT_NAME, AZURE_STORAGE_ACCOUNT_KEY, …). container
is the blob container name.
Build a store from an already-constructed object_store::ObjectStore. The
escape hatch when the *_from_env builders aren’t enough — pass anything
object_store can build (custom endpoints, static credentials, retries, …).
Google Cloud Storage, credentials from the standard environment
(GOOGLE_SERVICE_ACCOUNT / GOOGLE_SERVICE_ACCOUNT_KEY / Application Default
Credentials).