remove unused plugins

lua/config/zen-mode.lua

@@ -1,15 +0,0 @@
-require("zen-mode").setup {
-  window = {
-    backdrop = 0.8, -- shade the backdrop of the Zen window. Set to 1 to keep the same as Normal
-    width = 120,
-    options = {
-      -- signcolumn = "no", -- disable signcolumn
-      -- number = false, -- disable number column
-      -- relativenumber = false, -- disable relative numbers
-      cursorline = false, -- disable cursorline
-      cursorcolumn = false, -- disable cursor column
-      foldcolumn = "0", -- disable fold column
-      list = false, -- disable whitespace characters
-    },
-  },
-}