dsh-queue-first-enter: Press Enter to Control Queue Message Routing

`dsh-queue-first-enter` is a DeepSeek Harness (DSH) Web plugin designed to address the inflexible message execution order when the agent is busy. When the editor is empty and the agent is running, pressing Enter routes the first message in the queue to the current turn, while Ctrl/Cmd+Enter retains its original functionality. It must be installed via the command line, requires dsh web 0.1.0-rc.6 or later, and is suitable for debugging and testing in regular sessions, allowing manual adjustment of queue priority.