First custom Analyser subclass in this game tree. PatternAnalyser
operates per-entry without cross-entry state, so pairing
'attempting to join' with 'allowed to join' per Steam ID requires a
bespoke pass over the log. The analyser counts attempts and allowed
events per Steam ID and emits a ConnectionFailureProblem for each
player whose attempt count exceeds their allowed count. Unmatched
'attempting to join used queue' rows are surfaced as failures in v1
because a long queue wait is indistinguishable from a real failure
without timing context.
