git diff美化

# Debian/Ubuntu
sudo apt install git-delta

# Arch Linux
sudo pacman -S git-delta

# MacOS (Homebrew)
brew install git-delta

git config --global core.pager "delta"
git config --global interactive.diffFilter "delta --color-only"
git config --global delta.navigate true
git config --global delta.line-numbers true
git config --global delta.syntax-theme Dracula  # 或 OneHalfDark, Monokai, etc.
git config --global delta.side-by-side true     # 左右对比