Add Elo rating system with match entry and CSV upload

- Implement EloCalculator service for 2v2 Euchre matches
- Create background job processing with GoodJob
- Add single match entry form
- Add CSV upload for batch match entry
- Create player rankings view
- Add database schema for matches and elo snapshots

config/app.rb

@@ -1,8 +1,13 @@
 # frozen_string_literal: true
 
 require "hanami"
+require "good_job"
 
 module EuchreCamp
   class App < Hanami::App
+    config.root = File.expand_path("..", __dir__)
+
+    # Enable sessions
+    config.actions.sessions = :cookie, {secret: ENV.fetch("SESSION_SECRET", "change_me_in_production")}
   end
 end