dsh-antigravity-acp: Using Google Antigravity Models via ACP

`dsh-antigravity-acp` is a DeepSeek Harness (DSH) plugin that enables users to access the model directly through Google Antigravity's official ACP server, without cumbersome API key configuration. The plugin uses an MCP bridge to inject DSH's built-in tool capabilities (such as file operations and code execution) into the Antigravity context, enabling tool reuse. It supports automatic deployment, OAuth browser-based authorization, and concurrent processing, making it suitable for developers who need to leverage DSH's tool capabilities, but note that it only supports invoking tools through the bridge and runs with the privileges of the DSH process.