chore: move the go code into a subfolder

apps/api/internal/domain/mfa.go

@@ -0,0 +1,23 @@
+package domain
+
+import "github.com/zitadel/zitadel/internal/crypto"
+
+type MFAState int32
+
+const (
+	MFAStateUnspecified MFAState = iota
+	MFAStateNotReady
+	MFAStateReady
+	MFAStateRemoved
+
+	stateCount
+)
+
+type MultifactorConfigs struct {
+	OTP OTPConfig
+}
+
+type OTPConfig struct {
+	Issuer    string
+	CryptoMFA crypto.EncryptionAlgorithm
+}