Add ConnectionFailureAnalyser

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.

src/Analysis/ProjectZomboid/ConnectionFailureProblem.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace IndifferentKetchup\Codex\Analysis\ProjectZomboid;
+
+use IndifferentKetchup\Codex\Analysis\InsightInterface;
+use IndifferentKetchup\Codex\Analysis\Problem;
+
+/**
+ * Problem emitted by ConnectionFailureAnalyser when a player's
+ * "attempting to join" event count exceeds their "allowed to join" count
+ * within the same log file. Coalesced by Steam ID so each player produces
+ * at most one problem regardless of how many unmatched attempts they have.
+ */
+class ConnectionFailureProblem extends Problem
+{
+    private string $steamId = '';
+    private string $player = '';
+    private int $unmatchedAttempts = 0;
+
+    public function setSteamId(string $steamId): static
+    {
+        $this->steamId = $steamId;
+        return $this;
+    }
+
+    public function setPlayer(string $player): static
+    {
+        $this->player = $player;
+        return $this;
+    }
+
+    public function setUnmatchedAttempts(int $count): static
+    {
+        $this->unmatchedAttempts = $count;
+        return $this;
+    }
+
+    public function getSteamId(): string
+    {
+        return $this->steamId;
+    }
+
+    public function getPlayer(): string
+    {
+        return $this->player;
+    }
+
+    public function getUnmatchedAttempts(): int
+    {
+        return $this->unmatchedAttempts;
+    }
+
+    public function getMessage(): string
+    {
+        return sprintf(
+            'Player %s (%s) had %d "attempting to join" event(s) without a matching "allowed to join".',
+            $this->player,
+            $this->steamId,
+            $this->unmatchedAttempts
+        );
+    }
+
+    public function isEqual(InsightInterface $insight): bool
+    {
+        return $insight instanceof self && $insight->getSteamId() === $this->steamId;
+    }
+}