wrapNeovim start plugins expose colorscheme variants without setup

When Neovim plugins come from nixpkgs vimPlugins via wrapNeovimUnstable (plugins in packpath 'start'), adding catppuccin-nvim and tokyonight-nvim is enough: their colors/ dirs ship variant files, so :colorscheme catppuccin-mocha or tokyonight-moon works with no setup() call. Before switching away from gruvbox, grep the config for hardcoded hex colors in lualine/bufferline setup and for links to plugin-specific groups like GruvboxOrange (e.g. snacks dashboard). Those keep the old palette, or lose their color, under other colorschemes. Verify variant names with ls $(nix build --print-out-paths ...vimPlugins.<p>)/colors.