feat: Implement Frame.close() (#229)

* Implement `Frame.close()`

* close frame in dtor

* Update JImageProxyHostObject.cpp

* fix close

* Check if closed

* remove a few logs

* r

* fix `isValid` and `isReady`

* Add JImage

* Release JNI frame ref on destroy

* fix pod setup

* Fix isValid call

* Fix `close` not returning a function

* throw error if closed twice

* iOS: Schedule `console.error` call on JS thread

* Android: Log Frame Processor Error to JS

* fix syntax

* Check if valid `toString()`

* Update Frame.ts

* Remove `isReady`

* Fix JImage accessors

* remove `JImage` C++ sources

* Throw error if accessing props on closed Frame

* Delete `JImage.h`

android/src/main/java/com/mrousavy/camera/frameprocessor/ImageProxyUtils.java

@@ -0,0 +1,24 @@
+package com.mrousavy.camera.frameprocessor;
+
+import android.annotation.SuppressLint;
+import android.media.Image;
+import androidx.camera.core.ImageProxy;
+import com.facebook.proguard.annotations.DoNotStrip;
+
+public class ImageProxyUtils {
+    @SuppressLint("UnsafeOptInUsageError")
+    @DoNotStrip
+    public static boolean isImageProxyValid(ImageProxy imageProxy) {
+        try {
+            Image image = imageProxy.getImage();
+            if (image == null) return false;
+            // will throw an exception if the image is already closed
+            imageProxy.getImage().getCropRect();
+            // no exception thrown, image must still be valid.
+            return true;
+        } catch (Exception e) {
+            // exception thrown, image has already been closed.
+            return false;
+        }
+    }
+}