Structural shape of an AWS SESv2 client facade (injected or SDK-adapted). The
plugin never hard-depends on @aws-sdk/client-sesv2.
sendEmail(message: OutgoingMail): Promise<void>
Sends one message via SES.
Since 0.1.0
optional
isHealthy(): Promise<boolean>
M70c: reports whether the SES account is reachable — the real adapter
issues GetAccount. Optional so a minimal injected fake still
type-checks; a client that omits it is unknown, not false.