feat(lang): add luau support

lua/lazyvim/plugins/extras/lang/luau.lua

@@ -0,0 +1,72 @@
+local rojo_project
+
+return {
+  recommended = function()
+    return LazyVim.extras.wants({
+      ft = "luau",
+      root = {
+        ".luaurc",
+        ".config.luau",
+        "*.project.json",
+      },
+    })
+  end,
+
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = { ensure_installed = { "luau" } },
+  },
+
+  {
+    "neovim/nvim-lspconfig",
+    opts = {
+      servers = {
+        luau_lsp = {},
+      },
+      setup = {
+        luau_lsp = function(_, config)
+          -- luau-lsp.nvim configures it's own lsp so forward the config to it
+          vim.lsp.config("luau-lsp", config)
+          return true
+        end,
+      },
+    },
+  },
+
+  {
+    "stevearc/conform.nvim",
+    optional = true,
+    opts = {
+      formatters_by_ft = {
+        luau = { "stylua" },
+      },
+    },
+  },
+
+  {
+    "lopi-py/luau-lsp.nvim",
+    ft = "luau",
+    init = function()
+      rojo_project = vim.fs.root(0, function(name)
+        return name:match(".+%.project%.json$")
+      end)
+
+      if rojo_project then
+        vim.filetype.add({
+          extension = {
+            lua = function(path)
+              return path:match("%.nvim%.lua$") and "lua" or "luau"
+            end,
+          },
+        })
+      end
+    end,
+    opts = function()
+      return {
+        platform = {
+          type = rojo_project and "roblox" or "standard",
+        },
+      }
+    end,
+  },
+}