re-structure neovim plugins

also delete unused ones

config/nvim/lua/aleidk/plugins-core/init.lua

@@ -0,0 +1,14 @@
+return {
+	-- Detect tabstop and shiftwidth automatically
+	"tpope/vim-sleuth",
+	{ "nvim-tree/nvim-web-devicons", lazy = true },
+	{
+		-- Highlight word under cursor
+		"RRethy/vim-illuminate",
+		event = { "BufReadPost", "BufNewFile" },
+		opts = { delay = 200 },
+		config = function(_, opts)
+			require("illuminate").configure(opts)
+		end,
+	},
+}