AWS Transfer Family supports custom ports for public SFTP servers

Summary

• Transfer Family now supports configuring up to three custom ports (22 or 2000‑65535) for public SFTP servers.
• Each port can be set to client‑first or server‑first communication mode, improving compatibility with diverse client behaviors.
• Custom ports can reduce unwanted scans on port 22 and are configurable via console, CLI, or SDKs.