setAttributes method
Queue a batch of subscriber-attribute mutations. Written to the
local buffer immediately; the server sync happens in the background
(periodic tick, on foreground, or via flushAttributes). A null
value deletes the key. Reserved keys (prefixed with $, e.g.
$email) map to first-class fields server-side — setEmail/
setDisplayName/setPhoneNumber/setPushToken are thin wrappers
over this for the common ones.
Implementation
Future<void> setAttributes(Map<String, String?> attributes) => _platform.setAttributes(attributes);