dsh-codex-approval: DeepSeek Harness's Codex-style Approval Plugin

dsh-codex-approval is an MIT-licensed plugin for DeepSeek Harness (dsh) designed to address the issues of overly coarse or loose tool approval via a finer-grained decision chain. At the `approval/request` stage, the plugin introduces a three-layer mechanism: first, an explicit rule layer that supports matching by command or reason and setting allow, ask, or deny actions, with deny having the highest priority; second, an AI adjudication layer that evaluates risk and maps it to specific actions when rules do not match, supporting the configuration of the model, risk tolerance, and timeout policies; and finally, a human fallback to handle cases where the AI fails or requires confirmation. The plugin offers three modes: manual, ai, and ai-auto, with the latter automatically rejecting or approving pending requests.