Group member label improvements

ts/util/truncateString.std.ts

@@ -0,0 +1,25 @@
+// Copyright 2026 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { count, truncateAndSize } from './grapheme.std.js';
+import { isBodyTooLong, trimBody } from './longAttachment.std.js';
+
+export function truncateString(
+  target: string,
+  {
+    byteLimit,
+    graphemeLimit,
+  }: { byteLimit?: number; graphemeLimit?: number } = {}
+): string {
+  let result = target;
+
+  if (byteLimit && isBodyTooLong(result, byteLimit)) {
+    result = trimBody(result, byteLimit);
+  }
+
+  if (graphemeLimit && count(result) > graphemeLimit) {
+    [result] = truncateAndSize(result, graphemeLimit);
+  }
+
+  return result;
+}