Add selection types to TextInput onChange event (facebook#55043)

Summary:

This change adds TypeScript/Flow types and RNTester examples for the `selection` data in `TextInput.onChange` event.

This is the JS companion to the native changes that add selection data to the onChange event. 

## Why

On the web, text input elements provide `selectionStart` and `selectionEnd` properties that are always accessible during input events. This change exposes the selection data that native now provides, allowing developers to access cursor position during onChange.

## What Changed

1. **Flow Types**: Added optional `selection?: Selection` to `TextInputChangeEventData`
2. **TypeScript Types**: Updated `ReactNativeApi.d.ts` with selection type
3. **RNTester**: Updated examples to display selection in event logs

## Changelog

[General][Added] - TextInput onChange event types now include optional selection data

Differential Revision: D90123294

Author: alanleedev

packages/react-native/Libraries/Components/TextInput/TextInput.flow.js

@@ -29,6 +29,7 @@ type TextInputChangeEventData = $ReadOnly<{
   eventCount: number,
   target: number,
   text: string,
+  selection?: Selection,
 }>;
 
 export type TextInputChangeEvent =

packages/react-native/ReactNativeApi.d.ts

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<bffba0612c645ddb6166e1f5bb1187f2>>
+ * @generated SignedSource<<249ca589a73aaef41a965bcf3a2c0208>>
  *
  * This file was generated by scripts/js-api/build-types/index.js.
  */
@@ -5277,6 +5277,7 @@ declare type TextInputChangeEvent =
   NativeSyntheticEvent<TextInputChangeEventData>
 declare type TextInputChangeEventData = {
   readonly eventCount: number
+  readonly selection?: Selection
   readonly target: number
   readonly text: string
 }
@@ -6189,15 +6190,15 @@ export {
   TaskProvider, // 266dedf2
   Text, // e55ac2e2
   TextContentType, // 239b3ecc
-  TextInput, // cf7a3331
+  TextInput, // 2e89b91d
   TextInputAndroidProps, // 3f09ce49
-  TextInputChangeEvent, // 380cbe93
+  TextInputChangeEvent, // 6821f629
   TextInputContentSizeChangeEvent, // 5fba3f54
   TextInputEndEditingEvent, // 8c22fac3
   TextInputFocusEvent, // c36e977c
   TextInputIOSProps, // 0d05a855
   TextInputKeyPressEvent, // 967178c2
-  TextInputProps, // a817a7f7
+  TextInputProps, // c75f0362
   TextInputSelectionChangeEvent, // a1a7622f
   TextInputSubmitEditingEvent, // 48d903af
   TextLayoutEvent, // 45b0a8d7

packages/rn-tester/js/examples/TextInput/TextInputSharedExamples.js

@@ -393,7 +393,14 @@ class TextEventsExample extends React.Component<{...}, $FlowFixMe> {
           onFocus={() => this.updateText('onFocus')}
           onBlur={() => this.updateText('onBlur')}
           onChange={event =>
-            this.updateText('onChange text: ' + event.nativeEvent.text)
+            this.updateText(
+              'onChange text: ' +
+                event.nativeEvent.text +
+                ', selection: ' +
+                (event.nativeEvent.selection != null
+                  ? JSON.stringify(event.nativeEvent.selection)
+                  : 'undefined'),
+            )
           }
           onContentSizeChange={event =>
             this.updateText(