feat: Hosted login translation API (#10011)

# Which Problems Are Solved

This PR implements https://github.com/zitadel/zitadel/issues/9850

# How the Problems Are Solved

  - New protobuf definition
  - Implementation of retrieval of system translations
- Implementation of retrieval and persistence of organization and
instance level translations

# Additional Context

- Closes #9850

# TODO

- [x] Integration tests for Get and Set hosted login translation
endpoints
- [x] DB migration test
- [x] Command function tests
- [x] Command util functions tests
- [x] Query function test
- [x] Query util functions tests

internal/repository/org/eventstore.go

@@ -114,4 +114,5 @@ func init() {
 	eventstore.RegisterFilterEventMapper(AggregateType, NotificationPolicyAddedEventType, NotificationPolicyAddedEventMapper)
 	eventstore.RegisterFilterEventMapper(AggregateType, NotificationPolicyChangedEventType, NotificationPolicyChangedEventMapper)
 	eventstore.RegisterFilterEventMapper(AggregateType, NotificationPolicyRemovedEventType, NotificationPolicyRemovedEventMapper)
+	eventstore.RegisterFilterEventMapper(AggregateType, HostedLoginTranslationSet, HostedLoginTranslationSetEventMapper)
 }

internal/repository/org/hosted_login_translation.go

@@ -0,0 +1,55 @@
+package org
+
+import (
+	"context"
+
+	"golang.org/x/text/language"
+
+	"github.com/zitadel/zitadel/internal/eventstore"
+	"github.com/zitadel/zitadel/internal/zerrors"
+)
+
+const (
+	HostedLoginTranslationSet = orgEventTypePrefix + "hosted_login_translation.set"
+)
+
+type HostedLoginTranslationSetEvent struct {
+	eventstore.BaseEvent `json:"-"`
+
+	Translation map[string]any `json:"translation,omitempty"`
+	Language    language.Tag   `json:"language,omitempty"`
+	Level       string         `json:"level,omitempty"`
+}
+
+func NewHostedLoginTranslationSetEvent(ctx context.Context, aggregate *eventstore.Aggregate, translation map[string]any, language language.Tag) *HostedLoginTranslationSetEvent {
+	return &HostedLoginTranslationSetEvent{
+		BaseEvent:   *eventstore.NewBaseEventForPush(ctx, aggregate, HostedLoginTranslationSet),
+		Translation: translation,
+		Language:    language,
+		Level:       string(aggregate.Type),
+	}
+}
+
+func (e *HostedLoginTranslationSetEvent) Payload() any {
+	return e
+}
+
+func (e *HostedLoginTranslationSetEvent) UniqueConstraints() []*eventstore.UniqueConstraint {
+	return nil
+}
+
+func (e *HostedLoginTranslationSetEvent) Fields() []*eventstore.FieldOperation {
+	return nil
+}
+
+func HostedLoginTranslationSetEventMapper(event eventstore.Event) (eventstore.Event, error) {
+	translationSet := &HostedLoginTranslationSetEvent{
+		BaseEvent: *eventstore.BaseEventFromRepo(event),
+	}
+	err := event.Unmarshal(translationSet)
+	if err != nil {
+		return nil, zerrors.ThrowInternal(err, "ORG-BH82Eb", "unable to unmarshal hosted login translation set event")
+	}
+
+	return translationSet, nil
+}