vlln/dsh-loop: Adding timed loop capability to DSH

`vlln/dsh-loop` is a plugin used for scheduled loop execution in the DSH environment, designed to address scenarios such as periodically checking status and following up on unfinished tasks. The plugin provides services through the `/loop` command, the `loop` tool, and an active status bar at the top of the chat page, supporting the concurrent running of multiple loops within a single session. Its core functionality allows the model side to perform operations such as starting, stopping, viewing status, and listing loops via the `loop` tool, with the ability to dynamically adjust parameters based on the status of each round; on the user side, the `/loop` command enables flexible management of loop creation, listing, and termination. In terms of deployment, the plugin requires Node.js >=22.19.0 and DSH >=0.1.0-rc.5, and can be installed to the `web` profile via Git or NPM sources. After installation