refactor migrations sql scripts

migrations/20240530193519_typen.up.sql

@@ -1,4 +1,6 @@
 CREATE TABLE IF NOT EXISTS typen (
     id UUID PRIMARY KEY,
-    typname VARCHAR NOT NULL
+    typname VARCHAR NOT NULL,
+    erstellt_am TIMESTAMP WITH TIME ZONE NOT NULL,
+    geaendert_am TIMESTAMP WITH TIME ZONE NOT NULL
 );