dsh-web-restart: Restart the DSH Web Service from the Interface

The `dsh-web-restart` plugin provides a service restart entry point in the UI. It uses an independent supervisor process to stop and start the host process, resolving the need for manual restarts after upgrades. The plugin supports status monitoring, restart confirmation, and crash self-healing, and can automatically restore interrupted sessions when enabled in the configuration. Installation requires deploying a supervisor script and configuring launchd to support true restarts.