Persist pet profile changes via PATCH /api/portal/pets/{petId}

- handlePetSave is now async; calls PATCH before updating local state
- API response used as source of truth for local state update
- Error state shown on API failure; edit form NOT cleared on failure
- Loading/saving indicator in PetForm while API call in flight

Refs: GRO-1470
Co-Authored-By: Paperclip <noreply@paperclip.ing>

src/portal/sections/PetProfiles.tsx

@@ -83,9 +83,27 @@ export function PetProfiles({ sessionId, readOnly }: Props) {
   const petHistory = appointments.appointments.filter(a => a.pet?.id === selectedPetId && new Date(a.startTime) <= new Date());
   const editingPet = editingPetId ? pets.find(p => p.id === editingPetId) ?? null : null;
 
-  function handlePetSave(updatedPet: Pet) {
-    setPets(prev => prev.map(p => p.id === updatedPet.id ? updatedPet : p));
-    setEditingPetId(null);
+  const [saving, setSaving] = useState(false);
+  const [saveError, setSaveError] = useState<string | null>(null);
+
+  async function handlePetSave(updatedPet: Pet) {
+    setSaving(true);
+    setSaveError(null);
+    try {
+      const res = await fetch(`/api/portal/pets/${updatedPet.id}`, {
+        method: "PATCH",
+        headers: { "Content-Type": "application/json", ...buildHeaders(sessionId) },
+        body: JSON.stringify(updatedPet),
+      });
+      if (!res.ok) throw new Error("Failed to save pet");
+      const saved: Pet = await res.json();
+      setPets(prev => prev.map(p => p.id === saved.id ? saved : p));
+      setEditingPetId(null);
+    } catch (e) {
+      setSaveError(e instanceof Error ? e.message : "Failed to save pet");
+    } finally {
+      setSaving(false);
+    }
   }
 
   if (editingPet) {
@@ -94,6 +112,8 @@ export function PetProfiles({ sessionId, readOnly }: Props) {
         pet={editingPet}
         onSave={handlePetSave}
         onCancel={() => setEditingPetId(null)}
+        saving={saving}
+        saveError={saveError}
       />
     );
   }