Green interrupt button for DeepSeek Harness WebUI

Key features

• Green button in the composer tool row, right beside the send button
• Strong pauseaborts the active turn (model request / tool calls), kills background jobs and terminals owned by the agent, interrupts child agents, and disarms an armed goal so automatic continuation stops
• queued messages are preserved (keepInbox)
• The agent replies as an assistant message: stops, summarizes its progress in a few sentences, and asks for your new requirements
• ✎ Customizable interrupt promptedit the model-facing instruction in a dialog (available when nothing is active)