chore: move the go code into a subfolder

apps/api/internal/domain/instance.go

@@ -0,0 +1,23 @@
+package domain
+
+const (
+	IAMID = "IAM"
+)
+
+type InstanceState int32
+
+const (
+	InstanceStateUnspecified InstanceState = iota
+	InstanceStateActive
+	InstanceStateRemoved
+
+	instanceStateCount
+)
+
+func (s InstanceState) Valid() bool {
+	return s >= 0 && s < instanceStateCount
+}
+
+func (s InstanceState) Exists() bool {
+	return s != InstanceStateUnspecified && s != InstanceStateRemoved
+}