Stage 11: account linking & merge (email + Telegram Login Widget) (#12)

backend/internal/session/service.go

@@ -71,3 +71,14 @@ func (svc *Service) Revoke(ctx context.Context, token string) error {
 	svc.cache.Remove(hash)
 	return nil
 }
+
+// RevokeAllForAccount revokes every active session of accountID and evicts them
+// from the cache. The account-merge flow calls it to retire a secondary account
+// (Stage 11). It is idempotent.
+func (svc *Service) RevokeAllForAccount(ctx context.Context, accountID uuid.UUID) error {
+	if _, err := svc.store.RevokeAllForAccount(ctx, accountID, time.Now().UTC()); err != nil {
+		return err
+	}
+	svc.cache.RemoveByAccount(accountID)
+	return nil
+}