Move lsp config to local file structure

.config/nvim/lsp/selene3p_ls.lua

@@ -0,0 +1,12 @@
+---@brief
+---
+--- https://github.com/antonk52/lua-3p-language-servers
+---
+--- 3rd party Language Server for Selene lua linter
+
+---@type vim.lsp.Config
+return {
+  cmd = { 'selene-3p-language-server' },
+  filetypes = { 'lua' },
+  root_markers = { 'selene.toml' },
+}