Reintroduce inline metadata with full RTL support

ts/components/conversation/MessageTextMetadataSpacer.tsx

@@ -0,0 +1,13 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ReactElement } from 'react';
+import React from 'react';
+
+const SPACING = 10;
+
+export const MessageTextMetadataSpacer = ({
+  metadataWidth,
+}: Readonly<{ metadataWidth: number }>): ReactElement => (
+  <span style={{ display: 'inline-block', width: metadataWidth + SPACING }} />
+);