fix(ios): center RNNReactButtonView inside navigation bar platter

On iOS 26 the internal _UITAMICAdaptorView wrapper is wider than the
React button content and UIKit pins the custom view to the leading edge.
This makes the button icon/text appear off-center within the circular
Liquid Glass platter.

Apply a one-time horizontal CGAffineTransform in layoutSubviews to
shift the view to the center of its wrapper.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: IsaacIsrael

ios/RNNReactButtonView.mm

@@ -4,6 +4,7 @@
 @implementation RNNReactButtonView {
     NSLayoutConstraint *_widthConstraint;
     NSLayoutConstraint *_heightConstraint;
+    BOOL _didCenter;
 }
 
 - (instancetype)initWithHost:(RCTHost *)host
@@ -22,6 +23,7 @@ - (instancetype)initWithHost:(RCTHost *)host
     _heightConstraint.priority = UILayoutPriorityDefaultHigh;
     _widthConstraint.active = YES;
     _heightConstraint.active = YES;
+    _didCenter = NO;
     return self;
 }
 
@@ -41,6 +43,19 @@ - (void)updateConstraintsToFitSize {
     }
 }
 
+- (void)layoutSubviews {
+    [super layoutSubviews];
+    if (!_didCenter && self.superview && self.frame.size.width > 0) {
+        CGFloat wrapperWidth = self.superview.bounds.size.width;
+        CGFloat selfWidth = self.frame.size.width;
+        if (wrapperWidth > selfWidth) {
+            _didCenter = YES;
+            CGFloat tx = (wrapperWidth - selfWidth) / 2.0;
+            self.layer.affineTransform = CGAffineTransformMakeTranslation(tx, 0);
+        }
+    }
+}
+
 - (NSString *)componentType {
 	return ComponentTypeButton;
 }