feat(extras): added twig language (#5464)

## Description

Adds Twig templates language support as en extra.

Explanation for the tools choices:
- Linter/formatter: Twigcs and Twig-cs-fixer both follow the [coding
standards](https://twig.symfony.com/doc/3.x/coding_standards.html)
recommended by the Symfony Project, maintainers of Twig.
- LSP: I don't know it Twiggy is considered a standard in the community.
I picked it because it's the only server specific to Twig. The other
options are HTML servers that also include support for several templates
languages. I've been using it for a while and it works fine. It adds
much needed snippets (Twig syntax involves tags that are difficult to
type on most keyboards) and does not conflict with Twigcs diagnostics.

## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

---------

Co-authored-by: tw <tw@pretexx.fr>

lua/lazyvim/plugins/extras/lang/twig.lua

@@ -0,0 +1,58 @@
+return {
+  recommended = function()
+    return LazyVim.extras.wants({
+      ft = "twig",
+    })
+  end,
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = { ensure_installed = { "twig" } },
+  },
+  {
+    "williamboman/mason.nvim",
+    opts = {
+      ensure_installed = {
+        "twigcs",
+        "twig-cs-fixer",
+      },
+    },
+  },
+  {
+    "neovim/nvim-lspconfig",
+    opts = {
+      servers = {
+        twiggy_language_server = {
+          enabled = true,
+        },
+      },
+    },
+  },
+  {
+    "nvimtools/none-ls.nvim",
+    optional = true,
+    opts = function(_, opts)
+      local nls = require("null-ls")
+      opts.sources = opts.sources or {}
+      table.insert(opts.sources, nls.builtins.diagnostics.twigcs)
+      -- Twig-CS-Fixer builtin not available in none-ls
+    end,
+  },
+  {
+    "mfussenegger/nvim-lint",
+    optional = true,
+    opts = {
+      linters_by_ft = {
+        twig = { "twigcs" },
+      },
+    },
+  },
+  {
+    "stevearc/conform.nvim",
+    optional = true,
+    opts = {
+      formatters_by_ft = {
+        twig = { "twig-cs-fixer" },
+      },
+    },
+  },
+}