dsh-files-fallback: DSH's multi-type file attachments and desktop zero-copy reference plugin

File Reference and Attachment Plugin for DSH Web GUI, Maintainer: xinstart-1, Version 0.9.12, MIT License. It offers unified entry points via Drag & Drop, Ctrl+V Paste, and the 📎 Button, allowing any file type. On the browser side, files are persisted to the session workspace `.dsh-file-attachment/` via Host, referenced using `@absolute_path` chips (readable by text models). Duplicate handling includes appending `-N` and deduplication by name and size, with a 50MB limit per file. Inside the desktop shell, after obtaining the real OS path via Electron webUtils, files are referenced with zero-copy as `@original_path`, supporting no size limit, directories, and large files. It explicitly reports "File not found" if a file is moved or deleted. For non-multimodal models, a vision model generates a Chinese image description to fill the draft. Models can be selected from the harness model directory or configured with a Base URL + API Key for OpenAI-compatible endpoints; the agent can call the `describe_image` tool. Persisted attachments are permanently retained by default and can be cleaned up based on reference counts using the delete session plugin. To install, run `dsh plugin --profile web add ./dsh-files-fallback`.