feat: add custom timepicker option for overriding the default

packages/flutter_availability/lib/src/config/availability_options.dart

@@ -18,6 +18,7 @@ class AvailabilityOptions {
     this.spacing = const AvailabilitySpacing(),
     this.textStyles = const AvailabilityTextStyles(),
     this.colors = const AvailabilityColors(),
+    this.timePickerBuilder,
     AvailabilityDataInterface? dataInterface,
   }) : dataInterface = dataInterface ?? LocalAvailabilityDataInterface();
 
@@ -48,6 +49,10 @@ class AvailabilityOptions {
 
   /// The colors used in the userstory
   final AvailabilityColors colors;
+
+  /// A way to provide your own time picker implementation or customize
+  /// the default time picker
+  final TimePickerBuilder? timePickerBuilder;
 }
 
 /// All configurable paddings and whitespaces withing the userstory
@@ -137,3 +142,9 @@ typedef ButtonBuilder = Widget Function(
   FutureOr<void>? Function()? onPressed,
   Widget child,
 );
+
+/// Builder definition for providing a time picker implementation
+typedef TimePickerBuilder = Future<TimeOfDay?> Function(
+  BuildContext context,
+  TimeOfDay? initialTime,
+);

packages/flutter_availability/lib/src/ui/widgets/input_fields.dart

@@ -24,10 +24,12 @@ class TimeInputField extends StatelessWidget {
     var translations = options.translations;
 
     Future<void> onFieldtap() async {
-      var time = await showTimePicker(
+      var initialTime = TimeOfDay.fromDateTime(initialValue ?? DateTime.now());
+      var time = await (options.timePickerBuilder?.call(context, initialTime) ??
+          showTimePicker(
             context: context,
             initialTime: TimeOfDay.fromDateTime(initialValue ?? DateTime.now()),
-      );
+          ));
       if (time != null) {
         onTimeChanged(
           DateTime(