feat(tournaments): add partnership tracking and tournament management

Implement comprehensive partnership tracking system and tournament
management features including round-robin, single/double elimination,
and Swiss system pairings.

Changes:
- Add partnership_games and partnership_stats tables
- Implement PartnershipTracker service for recording partnership data
- Add tournament generator with multiple formats
- Create tournament management actions and views
- Add acceptance tests for partnership tracking
- Fix PartnershipTracker to use single snapshot per player per match
- Fix round-robin test to query by round_number instead of hardcoded ID

Note: All 8 acceptance tests now passing

db/migrate/20240915000002_enhance_events.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+ROM::SQL.migration do
+  change do
+    # Add new columns to events table
+    alter_table :events do
+      add_column :description, String
+      add_column :event_date, DateTime
+      add_column :event_type, String, default: 'tournament'
+      add_column :format, String, default: 'single_elim'
+      add_column :status, String, default: 'planned'
+      add_column :max_participants, Integer
+      add_column :created_at, DateTime, null: false, default: Sequel::CURRENT_TIMESTAMP
+      add_column :updated_at, DateTime, null: false, default: Sequel::CURRENT_TIMESTAMP
+    end
+
+    # Remove the self-referential column that's not being used
+    # (keeping it for potential nested tournaments in future)
+    # alter_table :events do
+    #   drop_column :event_id
+    # end
+  end
+end