hasUserSeenMessage method
Checks if the user has seen a message.
Implementation
Future<bool> hasUserSeenMessage(String roomId, String messageId) async {
final fu = firebaseUser;
if (fu == null) return false;
/// Fetch the current message document
final messageDoc = await getFirebaseFirestore()
.collection('${config.roomsCollectionName}/$roomId/messages')
.doc(messageId)
.get();
if (!messageDoc.exists) return false;
/// Get the current `seenBy` map
final seenBy = messageDoc.data()?['seenBy'] as Map<String, dynamic>? ?? {};
/// Check if the current user has already seen the message
return seenBy.containsKey(fu.uid);
}