fix(ios): preserve Liquid Glass on iOS 26 by skipping custom UITabBarAppearance

On iOS 26, creating a custom UITabBarAppearance replaces the
system-provided Liquid Glass material. This adds an early return in
updateTabBarAppearance() on iOS 26+ when no explicit barTintColor or
opaque scrollEdgeAppearance is set, so the system renders Liquid Glass
instead.

The inactive tint color is still applied via tabBar.unselectedItemTintColor
for apps that set tabBarInactiveTintColor.

Fixes #439

Author: deepak0x

packages/react-native-bottom-tabs/ios/TabViewImpl.swift

@@ -117,6 +117,15 @@ struct TabViewImpl: View {
 
     tabBar.isHidden = props.tabBarHidden
 
+    if #available(iOS 26.0, *) {
+      if props.barTintColor == nil && props.scrollEdgeAppearance != "opaque" {
+        if let inactiveTintColor = props.inactiveTintColor {
+          tabBar.unselectedItemTintColor = inactiveTintColor
+        }
+        return
+      }
+    }
+
     if props.scrollEdgeAppearance == "transparent" {
       configureTransparentAppearance(tabBar: tabBar, props: props)
       return