Fix uncontrolled multiline TextInput not expanding on iOS (#59417)

Summary:

Fixes an issue where on iOS, multiline expanding TextInputs do not expand if the input starts off as empty and uncontrolled.

### Root Cause

When a multiline TextInput on iOS is provided a `value` and `onChange()` prop, as shown in the [React Native docs](https://reactnative.dev/docs/textinput), the input grows as expected. However, uncontrolled inputs do not grow past the first initial line.

On mount, `BaseTextInputShadowNode::updateStateIfNeeded()` writes state only if the text changes, so the first state write is skipped for empty, uncontrolled inputs. As a result, `TextAttributes` keeps the default `fontSizeMultiplier = NaN` which is carried over since iOS copies the previous state for subsequent keystrokes. During measurement, `attributedStringBoxToMeasure()` sees that the current multiplier doesn't match the stored multiplier of NaN and falls back to `props.text` which is empty for uncontrolled inputs. This causes the input to stay one-line tall.

### This PR

Modify `BaseTextInputShadowNode::updateStateIfNeeded()` to update the state if base text attributes differ. On mount, the default font multiplier of NaN now differs from the real multiplier, so a state update occurs and the text field grows normally.

Changelog: [iOS][Fixed] - Fix multiline TextInput not growing with its content when uncontrolled and initially empty

Reviewed By: vzaidman

Differential Revision: D127048714

Author: jasozh

packages/react-native/ReactCommon/react/renderer/components/textinput/BaseTextInputShadowNode.h

@@ -157,7 +157,9 @@ class BaseTextInputShadowNode
     const auto &stateData = BaseShadowNode::getStateData();
     const auto &reactTreeAttributedString = getAttributedString(layoutContext);
 
-    if (stateData.reactTreeAttributedString.isContentEqual(reactTreeAttributedString)) {
+    if (stateData.reactTreeAttributedString.isContentEqual(reactTreeAttributedString) &&
+        stateData.reactTreeAttributedString.getBaseTextAttributes() ==
+            reactTreeAttributedString.getBaseTextAttributes()) {
       return;
     }