dsh-zgit: A Git Binary-Free Code Fetching Solution for DSH Agent

`dsh-zgit` is a dedicated plugin for DeepSeek Harness (DSH), designed to replace git operations and improve Agent runtime efficiency. It does not require a git binary; instead, it directly calls Forge’s HTTPS API to download source code and binary release files, and emulates git read commands such as `ls_tree`, `log`, and `diff`. The plugin supports SHA256 verification and byte-limit constraints to ensure security and compliance, making it suitable for code retrieval and resource deployment in git-free environments.