migration to mysql

.env.example

@@ -0,0 +1,12 @@
+# Database driver: mysql or sqlite (tests use sqlite)
+QDB_DRIVER=mysql
+
+# MySQL connection (required when QDB_DRIVER=mysql)
+QDB_MYSQL_HOST=127.0.0.1
+QDB_MYSQL_PORT=3306
+QDB_MYSQL_DATABASE=nat-as-db
+QDB_MYSQL_USER=nat_as_db
+QDB_MYSQL_PASSWORD=change-me
+
+# AES key for legacy SQLite file encryption and app payload crypto (32 bytes, base64)
+QDB_MASTER_KEY=