dsh-workspace-pin: Add official pinning for DSH sidebar workspace rows

DSH Web's sidebar session rows feature built-in pinning, whereas workspace rows lack this option. Users must rely on drag-and-drop sorting, and creating a new workspace disrupts the existing order. The extension 'dsh-workspace-pin' (maintained by Richard, version 0.3.0, MIT) ported the pinning mechanism from session rows to workspace rows. A 16x16 official-style button appears on hover; when pinned, a gray solid pin remains at the end of the row, utilizing the official Tooltip for the hover hint. The pinned collection is persisted to `state.json` by the host, ensuring it survives across browsers, incognito windows, and cache clearing. The host route reuses the official `requestRejection` authentication mechanism for writing. It employs temporary files with atomic rename operations for file updates. Since pin/unpin operations are incremental, concurrent pinning across different browsers will not overwrite each other. This article introduces the three platform commands for the installation script, verification methods, data location and reset procedures, implementation details, compatibility limitations, and the uninstallation process.