Treat NaN border widths as unset (#57789)

Summary:
Resetting a `borderWidth` on Android could clip or hide children in a rounded overflow-hidden view. The root cause is how a reset width is represented.

The border-width prop group is registered with `defaultFloat = Float.NaN` (ReactViewManager.kt), so removing `borderWidth` in JS calls the native setter with `Float.NaN`, not null. `BackgroundStyleApplicator.setBorderWidth` fans that value out to two consumers:

- the border drawable (via `width?.dpToPx() ?: Float.NaN`), which already treats `NaN` as unset.
- `BorderInsets`, which did not.

`BorderInsets.resolve()` falls back with the Elvis operator (`edgeInsets[...] ?: ... ?: 0f`), and `?:` only triggers on null. A non-null `NaN` edge is returned verbatim into the inset `RectF`, which produces a `NaN` content box and inner rounded clip, so children get clipped in overflow-hidden rounded views.

Fix: normalize `NaN` to unset in `BorderInsets.setBorderWidth` (`width?.takeUnless { it.isNaN() }`) so it falls back to the applicable all-edge width, matching what the drawable already does. `setBorderWidth` is the only mutator of the private `edgeInsets` array. `NaN` is never a meaningful width, so nothing legitimate is affected.

- Add a regression test confirming NaN edges fall back to the applicable all-edge width.

## Changelog:
[ANDROID] [FIXED] - Resetting border widths no longer clips children in rounded overflow-hidden views.

Fixes #57780

Pull Request resolved: #57789

Test Plan:
- Added `BorderInsetsTest.nanBorderWidthsAreTreatedAsUnset`.
- Android unit tests could not run locally because this environment has no configured Android SDK (`ANDROID_HOME`/`ANDROID_SDK_ROOT`).

Reviewed By: javache

Differential Revision: D114520650

Pulled By: fabriziocucci

fbshipit-source-id: 01afb38c8c5c0811e928e806d6912da5c3071804

Author: RealBhupesh

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/style/BorderInsets.kt

@@ -27,10 +27,10 @@ internal class BorderInsets {
    * Sets the border width for a specific logical edge.
    *
    * @param edge The logical edge to set
-   * @param width The border width in pixels, or null to clear
+   * @param width The border width in pixels, or null or NaN to clear
    */
   fun setBorderWidth(edge: LogicalEdge, width: Float?) {
-    edgeInsets[edge.ordinal] = width
+    edgeInsets[edge.ordinal] = width?.takeUnless { it.isNaN() }
   }
 
   /**

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/uimanager/style/BorderInsetsTest.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.uimanager.style
+
+import android.content.Context
+import android.util.LayoutDirection
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.kotlin.mock
+import org.robolectric.RobolectricTestRunner
+
+@RunWith(RobolectricTestRunner::class)
+class BorderInsetsTest {
+  @Test
+  fun nanBorderWidthsAreTreatedAsUnset() {
+    val borderInsets = BorderInsets()
+    borderInsets.setBorderWidth(LogicalEdge.ALL, 4f)
+    borderInsets.setBorderWidth(LogicalEdge.LEFT, Float.NaN)
+
+    val resolved = borderInsets.resolve(LayoutDirection.LTR, mock<Context>())
+
+    assertThat(resolved.left).isEqualTo(4f)
+    assertThat(resolved.top).isEqualTo(4f)
+    assertThat(resolved.right).isEqualTo(4f)
+    assertThat(resolved.bottom).isEqualTo(4f)
+  }
+}