feat(web): adopt MutationError across create/object forms; distinguish edit-form fetch error (#63)

web/src/fields/field-form.tsx

@@ -8,6 +8,7 @@ import {
   useVocabularies,
 } from "../api/queries";
 import { LabelEditor } from "../components/label-editor";
+import { MutationError } from "../components/mutation-error";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
@@ -95,7 +96,6 @@ export function FieldForm({
   };
 
   const pending = isEdit ? update.isPending : create.isPending;
-  const failed = isEdit ? update.isError : create.isError;
 
   return (
     <form onSubmit={onSubmit} className="space-y-3 overflow-auto p-4">
@@ -198,11 +198,7 @@ export function FieldForm({
           {t("form.required")}
         </p>
       )}
-      {failed && (
-        <p role="alert" className="text-xs text-destructive">
-          {t("form.rejected")}
-        </p>
-      )}
+      <MutationError error={isEdit ? update.error : create.error} />
 
       <Button type="submit" size="sm" disabled={pending}>
         {isEdit ? t("actions.save") : t("fields.create")}