REFACTOR: Updated from older config

lua/mason-conform/init.lua

@@ -1,13 +1,18 @@
 local M = {}
 
+---@class MasonConformConfig
+---@field ignore_install string[] Formatters that should never be installed automatically.
+
+---@type MasonConformConfig
 M.config = {
-    ignore_install = {}
+    ignore_install = {},
 }
 
-function M.setup(cfg)
-    if cfg and cfg.ignore_install then
-        M.config.ignore_install = cfg.ignore_install
-    end
+---@param opts? MasonConformConfig Options overriding the defaults.
+function M.setup(opts)
+    vim.validate("opts", opts, "table", true)
+
+    M.config = vim.tbl_deep_extend("force", { ignore_install = {} }, opts or {})
 
     require("mason-conform.auto_install")()
 end