feat: Custom message files (#1992)

* feat: add get custom message text to admin api

* feat: read custom message texts from files

* feat: get languages in apis

* feat: get languages in apis

* feat: get languages in apis

* feat: pr feedback

* feat: docs

* feat: merge main

internal/notification/repository/eventsourcing/view/custom_texts.go

@@ -0,0 +1,61 @@
+package view
+
+import (
+	"github.com/caos/zitadel/internal/errors"
+	"github.com/caos/zitadel/internal/eventstore/v1/models"
+	"github.com/caos/zitadel/internal/iam/repository/view"
+	"github.com/caos/zitadel/internal/iam/repository/view/model"
+	global_view "github.com/caos/zitadel/internal/view/repository"
+)
+
+const (
+	customTextTable = "notification.custom_texts"
+)
+
+func (v *View) CustomTextByIDs(aggregateID, template, lang, key string) (*model.CustomTextView, error) {
+	return view.CustomTextByIDs(v.Db, customTextTable, aggregateID, template, lang, key)
+}
+
+func (v *View) CustomTextsByAggregateIDAndTemplate(aggregateID, template string) ([]*model.CustomTextView, error) {
+	return view.GetCustomTextsByAggregateIDAndTemplate(v.Db, customTextTable, aggregateID, template)
+}
+
+func (v *View) CustomTextsByAggregateIDAndTemplateAndLang(aggregateID, template, lang string) ([]*model.CustomTextView, error) {
+	return view.GetCustomTexts(v.Db, customTextTable, aggregateID, template, lang)
+}
+
+func (v *View) PutCustomText(template *model.CustomTextView, event *models.Event) error {
+	err := view.PutCustomText(v.Db, customTextTable, template)
+	if err != nil {
+		return err
+	}
+	return v.ProcessedCustomTextSequence(event)
+}
+
+func (v *View) DeleteCustomText(aggregateID, textType, lang string, event *models.Event) error {
+	err := view.DeleteCustomText(v.Db, customTextTable, aggregateID, textType, lang)
+	if err != nil && !errors.IsNotFound(err) {
+		return err
+	}
+	return v.ProcessedCustomTextSequence(event)
+}
+
+func (v *View) GetLatestCustomTextSequence() (*global_view.CurrentSequence, error) {
+	return v.latestSequence(customTextTable)
+}
+
+func (v *View) ProcessedCustomTextSequence(event *models.Event) error {
+	return v.saveCurrentSequence(customTextTable, event)
+}
+
+func (v *View) UpdateCustomTextSpoolerRunTimestamp() error {
+	return v.updateSpoolerRunSequence(customTextTable)
+}
+
+func (v *View) GetLatestCustomTextFailedEvent(sequence uint64) (*global_view.FailedEvent, error) {
+	return v.latestFailedEvent(customTextTable, sequence)
+}
+
+func (v *View) ProcessedCustomTextFailedEvent(failedEvent *global_view.FailedEvent) error {
+	return v.saveFailedEvent(failedEvent)
+}