dsh-diff-card: DeepSeek Harness Single-Turn File Change Card

`dsh-diff-card` is a visualization plugin developed for DeepSeek Harness Desktop, designed to address the issue that logs make it difficult to confirm changes after an agent performs file operations. The plugin covers operations such as `edit` and `write`, provides a card-style display similar to Codex, and supports expanding or collapsing diffs, quick file navigation (such as opening files in VS Code), and undo or restore operations. The plugin interface automatically switches between Chinese and English, making it suitable for developers who require detailed code review or frequent rollbacks. The version requirement is >= 0.1.2-rc.1.