Last of the three items Rosmi720/XC_VM@8fa1e67f left over, deferred in
78d7b232 because the CRAP ratchet refuses hardening an uncovered cc=53
method. Extracting the guard instead of inlining it keeps the sniff happy
and gives the batch read a home the other six call sites can move to.
ResellerTableRenderer::handleLiveConnections iterated
RedisManager::instance()->mGet($rKeys) directly. RedisManager::instance()
returns null when Redis is unreachable, which makes that a fatal; mGet
answers false on a dropped connection and the client itself while
pipelining, which makes the foreach a warning; and a reseller with no
lines sends an empty key batch. Admin\TableController already carries the
guard — this moves it onto ConnectionTracker::readConnections(), which
already owns the LINE# reads two lines above.
Also swap the `array_multisort` order-column test to !empty(): the client
picks the column by index, so it can name the Responsive control column
(index 0, `false`) or one past the end of the map, and array_multisort on
an undefined key is a TypeError.
Verified: 869 tests, make gates, CRAP gate, PHPStan.
Refs: #148
