feat(extras): added ember lang support (#6203)

## Description

Added support for
[emberjs](https://guides.emberjs.com/release/getting-started/).

-
[nvim-lspconfig/ember](https://github.com/neovim/nvim-lspconfig/blob/master/lsp/ember.lua)
- Uses prettier to format glimmer files

## Checklist

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

lua/lazyvim/plugins/extras/lang/ember.lua

@@ -0,0 +1,29 @@
+return {
+  recommended = function()
+    return LazyVim.extras.wants({
+      ft = { "handlebars", "typescript", "javascript", "typescript.glimmer", "javascript.glimmer" },
+      root = { "ember-cli-build.js", ".git" },
+    })
+  end,
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = { ensure_installed = { "css", "glimmer", "glimmer_javascript", "glimmer_typescript" } },
+  },
+  {
+    "neovim/nvim-lspconfig",
+    opts = {
+      servers = {
+        ember = {},
+      },
+    },
+  },
+  {
+    "conform.nvim",
+    opts = function(_, opts)
+      if LazyVim.has_extra("formatting.prettier") then
+        opts.formatters_by_ft = opts.formatters_by_ft or {}
+        opts.formatters_by_ft.glimmer = { "prettier" }
+      end
+    end,
+  },
+}