Add getStreamFrameCount to retrieve captured frame count

Author: doblon8

src/main/java/io/github/doblon8/openpnp/capture/CaptureStream.java

@@ -64,6 +64,15 @@ public boolean hasNewFrame() {
         return result == 1;
     }
 
+    /**
+     * Get the number of frames captured during the lifetime of the stream.
+     *
+     * @return the number of frames captured during the lifetime of the stream.
+     */
+    public int getStreamFrameCount() {
+        return Cap_getStreamFrameCount(context.getSegment(), id);
+    }
+
     /**
      * Check if a stream is open, i.e. is capturing data.
      *