Add automatic user creation on database init

migrations/000_create_user.sql

@@ -0,0 +1,6 @@
+-- Create database user if not exists
+-- This runs automatically on container startup via docker-entrypoint-initdb.d
+
+CREATE USER IF NOT EXISTS 'amnezia'@'%' IDENTIFIED BY 'amnezia';
+GRANT ALL PRIVILEGES ON amnezia_panel.* TO 'amnezia'@'%';
+FLUSH PRIVILEGES;