Move lsp config to local file structure

.config/nvim/lsp/nushell.lua

@@ -0,0 +1,14 @@
+---@brief
+---
+--- https://github.com/nushell/nushell
+---
+--- Nushell built-in language server.
+
+---@type vim.lsp.Config
+return {
+  cmd = { 'nu', '--lsp' },
+  filetypes = { 'nu' },
+  root_dir = function(bufnr, on_dir)
+    on_dir(vim.fs.root(bufnr, { '.git' }) or vim.fs.dirname(vim.api.nvim_buf_get_name(bufnr)))
+  end,
+}