Add SQLite persistence, import-snapshot tool, and karma functionality

server/migrations/20260419083839_add_costume_lottery_effect_pending.sql

@@ -0,0 +1,12 @@
+-- +goose Up
+CREATE TABLE user_costume_lottery_effect_pending (
+    user_id           INTEGER NOT NULL REFERENCES users(user_id),
+    user_costume_uuid TEXT    NOT NULL,
+    slot_number       INTEGER NOT NULL,
+    odds_number       INTEGER NOT NULL DEFAULT 0,
+    latest_version    INTEGER NOT NULL DEFAULT 0,
+    PRIMARY KEY (user_id, user_costume_uuid)
+);
+
+-- +goose Down
+DROP TABLE IF EXISTS user_costume_lottery_effect_pending;