fix(ios): add log advice back when using shadow w/o a background (#57618)

Summary:
Back on old arch in RCTView.m we printed that warning:

https://github.com/react/react-native/blob/d13d2b0a5f7329d5fe9262259e8f846a86312f03/packages/react-native/React/Views/RCTView.m#L898-L906

This was missing on new arch and due to it we were missing some unoptimized views in our app which tanked performance.

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[IOS] [ADDED] - Print warning advice when using `shadow*` styles without providing a solid background color

Pull Request resolved: #57618

Test Plan: In rn-tester go to APIs > Box Shadow example to see the warnings printed!

Reviewed By: shwanton

Differential Revision: D113008257

Pulled By: fabriziocucci

fbshipit-source-id: 912224c426641325e010ebf261ea56f0b5dfa085

Author: hannojg

packages/react-native/React/Fabric/Mounting/ComponentViews/View/RCTViewComponentView.mm

@@ -21,6 +21,7 @@
 #import <React/RCTConversions.h>
 #import <React/RCTLinearGradient.h>
 #import <React/RCTLocalizedString.h>
+#import <React/RCTLog.h>
 #import <React/RCTRadialGradient.h>
 #import <react/featureflags/ReactNativeFeatureFlags.h>
 #import <react/renderer/components/view/ViewComponentDescriptor.h>
@@ -1009,6 +1010,13 @@ - (void)invalidateLayer
     } else {
       // Can't accurately calculate box shadow, so fall back to pixel-based shadow.
       layer.shadowPath = nil;
+
+      RCTLogAdvice(
+          @"View #%ld of type %@ has a shadow set but cannot calculate "
+           "shadow efficiently. Consider setting a solid background color to "
+           "fix this or applying the shadow to a more specific component.",
+          (long)self.tag,
+          [self class]);
     }
   } else {
     layer.shadowPath = nil;