fix: Convert Date to string for all remaining date fields in stock pages

app/(main)/stock/commandes/page.tsx

@@ -647,7 +647,7 @@ const CommandesPage = () => {
                                 <Calendar
                                     id="dateCommande"
                                     value={order.dateCommande}
-                                    onChange={(e) => setOrder({...order, dateCommande: e.value || new Date()})} 
+                                    onChange={(e) => setOrder({...order, dateCommande: e.value?.toISOString() || new Date().toISOString()})}
                                     showIcon
                                 />
                             </div>

app/(main)/stock/inventaire/page.tsx

@@ -593,7 +593,7 @@ const InventairePage = () => {
                                 <Calendar
                                     id="dateDebut"
                                     value={newSession.dateDebut}
-                                    onChange={(e) => setNewSession({...newSession, dateDebut: e.value || new Date()})} 
+                                    onChange={(e) => setNewSession({...newSession, dateDebut: e.value?.toISOString() || new Date().toISOString()})}
                                     showIcon
                                 />
                             </div>

app/(main)/stock/sorties/page.tsx

@@ -795,7 +795,7 @@ const SortiesPage = () => {
                                 <Calendar
                                     id="dateSortie"
                                     value={exit.dateSortie}
-                                    onChange={(e) => setExit({...exit, dateSortie: e.value || new Date()})} 
+                                    onChange={(e) => setExit({...exit, dateSortie: e.value?.toISOString() || new Date().toISOString()})}
                                     showIcon
                                 />
                             </div>