Mail Domain Check CLI v0.1.0

First public release of the dependency-free Mail Domain Check CLI.

• Checks MX, SPF, DKIM, DMARC, PTR, MTA-STS, TLS-RPT, and CAA
• Supports JSON output and Chinese text output
• Requires Node.js 20 or newer
• Sends only the supplied public domain, selector, and optional sending IP to the public scan API
• Includes a directly inspectable single-file CLI and an npm-format package archive