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

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

@@ -590,11 +590,11 @@ const InventairePage = () => {
 
                             <div className="field col-12 md:col-6">
                                 <label htmlFor="dateDebut">Date de début</label>
-                                <Calendar 
-                                    id="dateDebut" 
-                                    value={newSession.dateDebut} 
-                                    onChange={(e) => setNewSession({...newSession, dateDebut: e.value || new Date()})} 
-                                    showIcon 
+                                <Calendar
+                                    id="dateDebut"
+                                    value={newSession.dateDebut}
+                                    onChange={(e) => setNewSession({...newSession, dateDebut: e.value?.toISOString() || new Date().toISOString()})}
+                                    showIcon
                                 />
                             </div>