Function invalidateHomeCache

server/src/addie/home/cache.ts:95–103

(userId?: string)

 * Call this when user data changes (profile update, join working group, etc.)
 */
export function invalidateHomeCache(userId?: string): void {
  if (!homeContentCache) return;

  if (userId) {
    homeContentCache.invalidate(userId);
  } else {
    homeContentCache.clear();
  }
}