Add initial local archive export support.

core-util-jvm/src/main/java/org/signal/core/util/stream/NonClosingOutputStream.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2024 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.signal.core.util.stream
+
+import java.io.FilterOutputStream
+import java.io.OutputStream
+
+/**
+ * Wraps a provided [OutputStream] but ignores calls to [OutputStream.close] on it but will call [OutputStream.flush] just in case.
+ * Wrappers must call [OutputStream.close] on the passed in [wrap] stream directly.
+ */
+class NonClosingOutputStream(wrap: OutputStream) : FilterOutputStream(wrap) {
+  override fun close() {
+    flush()
+  }
+}