Перевод проекта на единую SQLite БД, WAL и обновление README для Windows

config/db/structure.sql

@@ -0,0 +1,14 @@
+CREATE TABLE `schema_migrations`(`filename` varchar(255) NOT NULL PRIMARY KEY);
+CREATE TABLE `cards`(
+  `id` integer NOT NULL PRIMARY KEY AUTOINCREMENT,
+  `name` varchar(255) NOT NULL,
+  `elixir_cost` integer NOT NULL,
+  `rarity` varchar(255),
+  `type` varchar(255),
+  `is_meta` integer DEFAULT(0),
+  `created_at` timestamp DEFAULT(datetime(CURRENT_TIMESTAMP, 'localtime')) NOT NULL,
+  `updated_at` timestamp DEFAULT(datetime(CURRENT_TIMESTAMP, 'localtime')) NOT NULL
+);
+INSERT INTO schema_migrations (filename) VALUES
+('20260303180000_create_cards.rb'),
+('20260303200000_enable_sqlite_wal.rb');