message: [client] Use a Set to prevent duplicates in `hashes()` function
  Follow-up to to use a Set instead of assuming the conflicting entry is at index 0, which is not always the case.
diff: @@ -58,9 +58,9 @@ export async function hashes(
  const entry = map.get(h);
  if (entry) {
  - if (entry.names[0] !== name) {
  - entry.names.push(name);
  - }
  + const names = new Set(entry.names);
  + names.add(name);
  + entry.names = [...names];
  } else {
  map.set(h, { names: [name], data, mode });
  }
  