/errors/product_link_error.proto

--- v16/errors/product_link_error.proto 2024-04-18 17:10:00.000000000 +0000
+++ v16-1/errors/product_link_error.proto   2024-04-18 17:10:09.000000000 +0000
@@ -46,5 +46,8 @@

     // A link cannot be created because a pending link already exists.
     INVITATION_EXISTS = 4;
+
+    // A link cannot be created because an active link already exists.
+    LINK_EXISTS = 5;
   }
 }