Add ent schema example

schema/ent/example/generate_schema.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"log"
+
+	"entgo.io/ent/entc"
+	"entgo.io/ent/entc/gen"
+)
+
+func main() {
+	log.Println("ersteller start")
+	must(entc.Generate("./schema/ent/example/ent/schema", &gen.Config{}))
+}
+
+func must(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}