fix: corregir payload de solicitud de servicio al backend

- day: usar formato ISO 8601 "yyyy-MM-dd" — @IsDateString() rechazaba
  el formato de DateTime.toString() que usa espacio en vez de T
- location_preference: enviar string "office"/"delivery" con la clave
  correcta — se enviaba 'location' con un entero (enum index)
- Construir el payload directamente en vez de usar Service.toDocument()
  que no coincide con CreateServiceDto

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/ui/views/dashboard_view.dart

@@ -370,26 +370,24 @@ class _DashboardViewState extends State<DashboardView> {
 
     setState(() => _requesting = true);
     try {
-      final service = Service(
-        id: null,
-        professionalId: _professional!.user.id,
-        professionalScored: false,
-        userId: user!.id,
-        userScored: false,
-        address: isOfficeOnly ? _professional!.professionalInfo.address : _currentAddress,
-        aditionalAddress: '',
-        latitude: isOfficeOnly ? _professional!.professionalInfo.latitude : _mapCenter.latitude,
-        longitude: isOfficeOnly ? _professional!.professionalInfo.longitude : _mapCenter.longitude,
-        day: _selectedDay.toString(),
-        createdAt: DateTime.now().toIso8601String(),
-        description: '',
-        range1Hour1: _selectedHour!,
-        range1Hour2: _selectedHour!.add(minute: _professional!.professionalInfo.slotDurationMinutes),
-        rate: '',
-        status: ServiceStatus.pending,
-        location: serviceLocation,
-      );
-      await ApiService.instance.post('/services', service.toDocument());
+      final slot = _selectedHour!;
+      final endSlot = slot.add(minute: _professional!.professionalInfo.slotDurationMinutes);
+      String pad(int n) => n.toString().padLeft(2, '0');
+
+      // Build payload matching CreateServiceDto exactly
+      final payload = {
+        'professional_id': _professional!.user.id,
+        // @IsDateString() expects ISO 8601 date — "yyyy-MM-dd"
+        'day': '${_selectedDay!.year}-${pad(_selectedDay!.month)}-${pad(_selectedDay!.day)}',
+        'range1_hour1': '${pad(slot.hour)}:${pad(slot.minute)}',
+        'range1_hour2': '${pad(endSlot.hour)}:${pad(endSlot.minute)}',
+        'address': isOfficeOnly ? _professional!.professionalInfo.address : _currentAddress,
+        'latitude': isOfficeOnly ? _professional!.professionalInfo.latitude : _mapCenter.latitude,
+        'longitude': isOfficeOnly ? _professional!.professionalInfo.longitude : _mapCenter.longitude,
+        // @IsEnum(['office','delivery']) expects the string value, not an integer
+        'location_preference': isOfficeOnly ? 'office' : 'delivery',
+      };
+      await ApiService.instance.post('/services', payload);
       NotificationsService.showSnackbar('Servicio solicitado exitosamente');
       if (_professional!.user.token != null) {
         LocalNotifications.sendPushNotification(