for better compatibility with scanners

Add fallback to use domain JID when commandJid is null. This fixes the
commands tab functionality for IRC servers where the commandJid was not
being properly set, causing the tab to not appear.

Fixes issue where Commands tab wouldn't show for IRC servers like
irc.libera.chat@irc.cheogram.com while working fine for IRC channels.

Fixes: https://todo.sr.ht/~singpolyma/soprani.ca/438
Assisted-by: Claude Sonnet 4.5 via Crush

Remove QuickConversationsService.isConversations() checks from
AppSettings.java (isUseTor, isExtendedConnectionOptions) to allow Tor
connections in non-Conversations flavours.

I tested by installing with a modified package ID, adding a new account,
enabling the Tor toggle, and seeing that 0 out of 1 accounts were
connected because Tor is unavailable. After installing/enabling Orbot
and waiting a bit, I had to toggle the account to get it to try again.

Fixes: https://todo.sr.ht/~singpolyma/soprani.ca/442

for better compatibility with scanners