• feat: Tighter safety on every ~/.ssh/config write.
• feat: Multi-key hosts keep every IdentityFile line when you edit one of them.
• feat: Vault SSH signing leaves your user-set CertificateFile lines exactly where they are.
• feat: Vault roles stay on the single host you targeted, even on shared Host A B lines.
• feat: Provider sync can never smuggle extra directives into your config through a crafted server name.
• feat: Self-including or mutually-including SSH config files terminate cleanly instead of hanging the parser.
• feat: Your most recent save survives a sudden power loss thanks to a durable rename on the underlying write.