dsh-self-preserve: Preventing Model Sessions from Stopping the Running Harness

dsh-self-preserve is a DeepSeek Harness plugin designed to prevent model sessions from unintentionally terminating the Harness process. It protects service integrity by intercepting self-terminating commands such as `systemctl stop` on Linux, or by setting an environment variable to intercept `launchd` stop commands on macOS. After installation, an external restart is required, and read-only access permissions for other services are preserved to ensure workflow stability.