Describes a file to upload via Client::upload_attachment. Provide the file
ONE of four ways (checked in this order): url, bytes, path, or
content (base64). retention_days optionally overrides how long the hosted
file lives.
Returned for any non-2xx response (or a local failure). status is the HTTP
status code (0 for a transport/local error), message is the API’s error
field when present, and body is the parsed response body when there was one.
Protect a UTF-8 plaintext to an RSA public key (SPKI PEM), returning the
at-rest envelope serialized as a compact JSON string. Hybrid scheme — a fresh
AES-256-GCM content key encrypts the data and is wrapped with RSA-OAEP
(SHA-256). Local only — no network call.
Verify the signature and reject events older than tolerance_ms (0 disables
the freshness check). Parses t=<ms>,v1=<hex> and checks
HMAC-SHA256(secret, "<t>.<payload>").