Moves seed genres to migration

db/migrate/20260413115611_seed_genres.rb

@@ -0,0 +1,20 @@
+class SeedGenres < ActiveRecord::Migration[8.1]
+  def change
+    # Create Genres
+    puts "Creating genres..."
+    genres = [
+      "Action", "Adventure", "RPG", "JRPG", "Strategy", "Simulation",
+      "Platformer", "Fighting", "Racing", "Sports", "Puzzle", "Horror",
+      "Stealth", "Shooter", "FPS", "TPS", "Rhythm", "Visual Novel",
+      "Roguelike", "Metroidvania", "Sandbox", "MMO", "Turn-Based",
+      "Real-Time Strategy", "Tower Defense", "Card Game", "Party Game",
+      "Educational", "Survival", "Battle Royale"
+    ]
+
+    genres.each do |genre_name|
+      Genre.find_or_create_by!(name: genre_name)
+    end
+
+    puts "Created #{Genre.count} genres"
+  end
+end