json: add configuration for JSON

- Adds the `json` parser to the treesitter languages for linting
  purpose.
- Adds `jsonls` as language server provider for JSON.
- Creates the `after/ftplugin` folders.
- Sets specific settings for JSON for folding method.

Co-Authored-by: iGor milhit <igor@milhit.ch>

after/ftplugin/json.lua

@@ -0,0 +1,8 @@
+-- Specific settings for JSON files
+--   Use treesitter for folding
+--   Disable the color column
+
+vim.opt.foldmethod="expr"
+vim.opt.foldexpr="nvim_treesitter#foldexpr()"
+vim.opt.foldlevel=3
+vim.opt.colorcolumn=""

init.lua

@@ -362,7 +362,7 @@ vim.keymap.set('n', '<leader>ss', require'telescope'.extensions.luasnip.luasnip
 -- See `:help nvim-treesitter`
 require('nvim-treesitter.configs').setup {
   -- Add languages to be installed here that you want installed for treesitter
-  ensure_installed = { 'c', 'cpp', 'go', 'lua', 'python', 'rust', 'tsx', 'typescript', 'vimdoc', 'vim' },
+  ensure_installed = { 'c', 'cpp', 'go', 'lua', 'python', 'rust', 'tsx', 'typescript', 'vimdoc', 'vim', 'json' },
 
   -- Autoinstall languages that are not installed. Defaults to false (but you can change for yourself!)
   auto_install = false,
@@ -516,6 +516,11 @@ local servers = {
       }
     }
   },
+
+  -- Require vscode-langservers-extracted
+  --   https://github.com/hrsh7th/vscode-langservers-extracted
+  jsonls = {
+  },
 }
 
 -- Setup neovim lua configuration