Add KDoc documentation to Overflow.kt

Summary:
Added KDoc documentation to Overflow.kt:

- Enum documentation explaining CSS overflow correspondence
- Documented each value: VISIBLE, HIDDEN, SCROLL
- Added fromString() method documentation

changelog: [internal] internal

Reviewed By: javache

Differential Revision: D91555087

Author: mdvacca

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

@@ -7,12 +7,27 @@
 
 package com.facebook.react.uimanager.style
 
+/**
+ * Enum representing the overflow behavior of a view's content.
+ *
+ * These values correspond to CSS overflow property values, controlling how content that exceeds the
+ * view's bounds is handled.
+ */
 internal enum class Overflow {
+  /** Content is not clipped and may be visible outside the view's bounds. */
   VISIBLE,
+  /** Content is clipped to the view's bounds without scrolling. */
   HIDDEN,
+  /** Content is clipped to the view's bounds but can be scrolled to reveal hidden content. */
   SCROLL;
 
   companion object {
+    /**
+     * Parses a string into an Overflow value.
+     *
+     * @param overflow The string value (case-insensitive)
+     * @return The corresponding Overflow, or null if not recognized
+     */
     @JvmStatic
     fun fromString(overflow: String): Overflow? {
       return when (overflow.lowercase()) {