extensions/umode_hide_idle_time: mask times for hidden sources

[aaronmdjones]

If the user performing a WHOIS has hidden their idle time (is umode +I), also prevent them from seeing other user's idle times, even if said users are not themselves umode +I.

Suggested-by: @Unit193

[aaronmdjones]

From a non-hidden user against a hidden user:

07:03:36 -!- Aaron|Hidden [~aaron@localhost]
07:03:36 -!-  ircname  : Aaron Jones
07:03:36 -!-  server   : hades.arpa [solanum test server]
07:03:36 -!-  idle     : 0 days 0 hours 0 mins 0 secs [signon: Mon Sep 26 07:02:57 2022]
07:03:36 -!-           : is using a private idle time
07:03:36 -!- End of WHOIS

From an oper against a hidden user:

07:04:25 -!- Aaron|Hidden [~aaron@localhost]
07:04:25 -!-  ircname  : Aaron Jones
07:04:25 -!-  server   : hades.arpa [solanum test server]
07:04:25 -!-  idle     : 0 days 0 hours 1 mins 28 secs [signon: Mon Sep 26 07:02:57 2022]
07:04:25 -!-           : is using a private idle time
07:04:25 -!- End of WHOIS

From self against a hidden user:

07:05:06 -!- Aaron|Hidden [~aaron@localhost]
07:05:06 -!-  ircname  : Aaron Jones
07:05:06 -!-  server   : hades.arpa [solanum test server]
07:05:06 -!-  idle     : 0 days 0 hours 2 mins 9 secs [signon: Mon Sep 26 07:02:57 2022]
07:05:06 -!-           : is using a private idle time
07:05:06 -!- End of WHOIS

From a hidden user against a non-hidden user:

07:07:12 -!- Aaron|Public [~aaron@localhost]
07:07:12 -!-  ircname  : Aaron Jones
07:07:12 -!-  server   : hades.arpa [solanum test server]
07:07:12 -!-  idle     : 0 days 0 hours 0 mins 0 secs [signon: Mon Sep 26 07:03:29 2022]
07:07:12 -!- End of WHOIS

[examknow]

I would be sure to note this caveat in the UMODE help