Refactored app to more explicitly require gems/modules that are used per-file

src/server.rb

@@ -1,17 +1,10 @@
 # frozen_string_literal: true
 
 require 'sinatra/base'
-require 'sinatra/json'
 
-# Base app
+# Server - base modular Sinatra app class
 class Server < Sinatra::Base
 
-  enable :sessions
-
-  # Set up static file serving
-  enable :static
-  set :public_folder, File.join(__dir__, '/../public')
-
   # Register view helpers
   require_relative 'helpers'
   helpers Helpers