irc: fix type of values in hashtables join_manual/join_noswitch, fix delay for purge
core: allow read of array in hdata without using index
irc: unmask smart filtered join if nick speaks in channel some minutes after the join, new option irc.look.smart_filter_join_unmask (task #12405)

The nick changes are tracked and will be unmasked with the join.
Events triggering the unmask of join are: a message (can be CTCP), a notice or
an update of topic.