OptionalregionAWS region, e.g. 'us-east-1'.
OptionalcredentialsStatic credentials. Omit to use the default AWS credential provider chain.
OptionalendpointOverride the service endpoint (e.g. 'http://localhost:4566' for LocalStack).
OptionalclientA pre-built SNSClient (or compatible object). When provided, connect()
uses it directly and does NOT require the SDK — this is how tests inject a
mock client.
Connection options for
SnsStore.