dsh-ide-git: IDE-Level Git Tool Window

The `dsh-ide-git` plugin is maintained by KannaKuron and is designed to provide DSH with a highly customized Git tool window. It integrates the branch tree, commit graph, changed files list, and commit details into an IDE-level panel, supports JetBrains-style operations, and works as a native tab that fits right-side or bottom panel layouts. Core features include branch management, commit topology visualization, line-by-line diff viewing, and AI collaboration (sending references/code snippets). The plugin supports operations such as staging, resetting, and cherry-picking, and includes safety mechanisms for serial execution of write operations as well as undoing deletions within 30 minutes. It requires host DSH version >= 0.1.6-alpha.2.