An inert file attachment or pre-uploaded provider file reference.
from_path/2 is the only local-path entry point and reads immediately.
Keeping the bytes in the value makes later adapter formatting, persistence,
retries, and service restarts independent of the original filesystem path.
Summary
Functions
Creates an attachment from raw bytes without performing I/O.
Creates an inert reference to a file already uploaded to a provider.
Reads a trusted local file immediately into a data-backed attachment.