Add db & pydantic models + set up alembic

backend/scripts/db_setup.sql

@@ -0,0 +1,7 @@
+-- Creates an user
+CREATE USER
+IF NOT EXISTS 'admin'@'%' IDENTIFIED BY '@Avatarme1';
+
+-- Grant rights to admin user
+GRANT ALL PRIVILEGES ON `CMT`.* TO 'admin'@'%';
+FLUSH PRIVILEGES;