Move lsp config to local file structure

.config/nvim/lsp/custom_elements_ls.lua

@@ -0,0 +1,32 @@
+---@brief
+---
+--- https://github.com/Matsuuu/custom-elements-language-server
+---
+--- `custom-elements-languageserver` depends on `typescript`. Both packages can be installed via `npm`:
+--- ```sh
+--- npm install -g typescript custom-elements-languageserver
+--- ```
+--- To configure typescript language server, add a
+--- [`tsconfig.json`](https://www.typescriptlang.org/docs/handbook/tsconfig-json.html) or
+--- [`jsconfig.json`](https://code.visualstudio.com/docs/languages/jsconfig) to the root of your
+--- project.
+--- Here's an example that disables type checking in JavaScript files.
+--- ```json
+--- {
+---   "compilerOptions": {
+---     "module": "commonjs",
+---     "target": "es6",
+---     "checkJs": false
+---   },
+---   "exclude": [
+---     "node_modules"
+---   ]
+--- }
+--- ```
+
+---@type vim.lsp.Config
+return {
+  init_options = { hostInfo = 'neovim' },
+  cmd = { 'custom-elements-languageserver', '--stdio' },
+  root_markers = { 'tsconfig.json', 'package.json', 'jsconfig.json', '.git' },
+}