fix(ui_kit): remove null check operator in Loader component

packages/wyatt_ui_kit/example/lib/loaders/loaders.dart

@@ -64,5 +64,4 @@ class Loaders extends DemoPage {
           const Gap(20),
         ],
       );
-      
 }

packages/wyatt_ui_kit/lib/src/components/loader/loader.dart

@@ -59,15 +59,14 @@ class Loader extends LoaderComponent with $LoaderCWMixin {
     final style = _resolve(context);
     final dimension =
         (radius != null) ? radius! * 2 : context.buttonTheme.height;
-
     return SizedBox.square(
       dimension: dimension,
       child: RepaintBoundary(
         child: CustomPaint(
           painter: _LoaderPainter(
-            style.colors!,
+            style.colors ?? const MultiColor([]),
             dimension / 2,
-            style.stroke!,
+            style.stroke ?? 4,
             flip: flip ?? false,
           ),
         )

packages/wyatt_ui_kit/lib/src/components/loader/loader_theme_resolver.dart

@@ -24,6 +24,12 @@ class LoaderThemeResolver
     required this.customStyleFn,
   });
 
+  @override
+  final LoaderStyle? Function(
+    BuildContext context, {
+    void extra,
+  }) customStyleFn;
+
   /// Values taken from <https://api.flutter.dev/flutter/material/ElevatedButton/defaultStyleOf.html>
   @override
   LoaderStyle computeDefaultValue(
@@ -39,12 +45,6 @@ class LoaderThemeResolver
         stroke: 4,
       );
 
-  @override
-  final LoaderStyle? Function(
-    BuildContext context, {
-    void extra,
-  }) customStyleFn;
-
   @override
   LoaderStyle? computeExtensionValueFn(
     BuildContext context,