refactor(mail): modernize smtp sending with go-mail and unify message gateway pusher

backend/core/contracts/push.go

@@ -6,6 +6,7 @@ package contracts
 
 import "context"
 
+// PushNotificationTemplate defines notification message template payload.
 type PushNotificationTemplate struct {
 	Title   string
 	Content string
@@ -13,6 +14,7 @@ type PushNotificationTemplate struct {
 	Ext     map[string]any
 }
 
+// PushEventMeta defines metadata for a system push event.
 type PushEventMeta struct {
 	Key             string
 	Name            string
@@ -20,6 +22,7 @@ type PushEventMeta struct {
 	DefaultTemplate PushNotificationTemplate
 }
 
+// PushRegistry defines the interface for registering built-in events.
 type PushRegistry interface {
 	RegisterBuiltInEvent(meta PushEventMeta)
 	SyncEvents(ctx context.Context) error

backend/core/extpoints/config_resolve.go

@@ -181,7 +181,7 @@ func formatEntryValue(value any, secret bool) string {
 		return ""
 	}
 	rv := reflect.ValueOf(value)
-	if rv.Kind() == reflect.Ptr {
+	if rv.Kind() == reflect.Pointer {
 		if rv.IsNil() {
 			return ""
 		}

backend/core/extpoints/config_value.go

@@ -33,7 +33,7 @@ func convertValue(raw any, typ reflect.Type) (any, error) {
 		return convertSlice(raw, typ)
 	case reflect.Struct:
 		return convertStruct(raw, typ)
-	case reflect.Ptr:
+	case reflect.Pointer:
 		return convertPointer(raw, typ)
 	default:
 		return nil, fmt.Errorf("%w: %s is not a supported configuration type", ErrConfigType, typ)
@@ -44,7 +44,7 @@ func convertValue(raw any, typ reflect.Type) (any, error) {
 // Nested pointers are rejected so configuration tags stay one level deep.
 func convertPointer(raw any, typ reflect.Type) (any, error) {
 	elemType := typ.Elem()
-	if elemType.Kind() == reflect.Ptr {
+	if elemType.Kind() == reflect.Pointer {
 		return nil, fmt.Errorf("%w: %s is not a supported configuration type", ErrConfigType, typ)
 	}
 	elem, err := convertValue(raw, elemType)