refactor: clean up user example files to be easier to follow

lua/plugins/colorscheme.lua

@@ -0,0 +1,8 @@
+if true then return {} end -- REMOVE THIS LINE TO ACTIVATE THIS FILE
+
+return {
+  "AstroNvim/astroui",
+  opts = {
+    colorscheme = "astrodark", -- change colorscheme
+  },
+}