dsh-editor-selection: Enabling DSH to Understand Editor Selections

`dsh-editor-selection` is a plugin in the DeepSeek Harness (DSH) ecosystem designed to address the challenge agents face in locating the user's selected code snippet. The plugin captures the editor's primary selection, including file path and line numbers, and injects it into the agent context as a structured environmental notice for precise alignment. Core features include “select to focus”, right-click explanation, and privacy controls. It uses local loopback communication, avoids cloud services, stores only data hashes, and follows the principle of least privilege. Users can install it via PowerShell and control state sharing through a toggle.