Update VideoGravity.

Author: shogo4405

haishinkit/src/main/java/com/haishinkit/graphics/VideoGravity.kt

@@ -1,13 +1,45 @@
 package com.haishinkit.graphics
 
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
 /**
- * A value that specifies how the video is displayed within a layer’s bounds.
+ * Specifies how a video is scaled or stretched to fit within its container bounds.
  */
 @Suppress("UNUSED")
+@Serializable
 enum class VideoGravity(
+    /**
+     * Platform-compatible integer representation of this gravity.
+     *
+     * This value is useful when bridging with native layers or
+     * when a numeric representation is required.
+     */
     val rawValue: Int,
 ) {
+    /**
+     * Stretches the video to fill the container bounds.
+     *
+     * The aspect ratio is not preserved.
+     */
+    @SerialName("resize")
     RESIZE(0),
+
+    /**
+     * Scales the video to fit within the container bounds
+     * while preserving the original aspect ratio.
+     *
+     * Black bars may appear if the aspect ratios do not match.
+     */
+    @SerialName("resizeAspect")
     RESIZE_ASPECT(1),
+
+    /**
+     * Scales the video to completely fill the container bounds
+     * while preserving the original aspect ratio.
+     *
+     * Portions of the video may be clipped if the aspect ratios do not match.
+     */
+    @SerialName("resizeAspectFill")
     RESIZE_ASPECT_FILL(2),
 }