nvim: Switch to zen-mode and twilight plugins

Switched out the old distraction-free writing plugins for neovim
variants zen-mode and twilight by folke - they are simple (one command
to invoke zen-mode, mapped to `F11`, and that's it), they are written in
lua and they work together beautifully (invoking zen-mode also invokes
twilight paragraph highlighting).

nvim/.config/nvim/lua/maps.lua

@@ -183,8 +183,7 @@ map.x.nore.silent['<localleader>q'] = 'gq'
 map.n.nore.silent['<localleader>Q'] = 'vapJgqap'
 
 -- Enter distraction free prose mode with F11
-map.n.nore.silent['<F11>'] = ':TZAtaraxis<cr>'
-map.n.nore.silent['<F10>'] = ':TZMinimalist<cr>'
+map.n.nore.silent['<F11>'] = ':ZenMode<cr>'
 
 -- PLUGIN: fzf-bibtex
 -- map @@ to automatically insert citation reference at cursor

nvim/.config/nvim/lua/plugins.lua

@@ -102,20 +102,8 @@ require("packer").startup(function()
         ft = { "quarto" }
     }
     use 'micarmst/vim-spellsync' -- personal dict improvements for git sync
-    use { -- provide distraction free writing
-        'Pocco81/TrueZen.nvim',
-        config = function()
-            require("true-zen").setup({
-                integrations = {
-                    gitsigns = true,
-                    lualine = true,
-                    tmux = { global = false },
-                    limelight = true
-                }
-            })
-        end
-    }
-    use { 'junegunn/limelight.vim', event = 'BufRead' } -- provide even distraction free-er writing (lowlight paragraphs)
+    use { 'folke/zen-mode.nvim', config = require('zen-mode').setup() } -- provide distraction free writing
+    use 'folke/twilight.nvim' -- provide even distraction free-er writing (lowlight paragraphs)
     use 'alok/notational-fzf-vim' -- quickly search through the wiki
 
     -- languages