dsh-steer-button: DeepSeek Harness Queue, Steering, and Backtracking Control

`dsh-steer-button` is an input stream control plugin for DeepSeek Harness, designed to address the limitations of default input behavior when fine-grained orchestration is required. It offers three delivery modes: Queue mode (messages are queued and wait), Steer mode (interrupts the current output), and Backlog mode (queues the entire turn). The plugin supports queue visualization, editing, and undo operations, and can manage pending queues through the stop-and-process feature. Installation requires specific version prerequisites and a restart of the configuration file. It is suitable for developers who need to dynamically adjust input streams and the timing of context injection.