Add ProjectZomboidCmdLog (cmd.txt)

Per-line client RPC trace. Parser captures only the timestamp;
analysers decompose steamid/player/command/coords via CmdPattern::FIELDS.
Detectors: filename match plus content signature on the
'steamid "name" command @ x,y,z' line shape.

src/Pattern/ProjectZomboid/CmdPattern.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace IndifferentKetchup\Codex\Pattern\ProjectZomboid;
+
+/**
+ * Regex constants for the Project Zomboid cmd.txt format.
+ *
+ *   [time] steamid "player" command @ x,y,z.
+ *
+ * LINE captures, in order:
+ *   1. time
+ */
+class CmdPattern
+{
+    public const string LINE = '/^\[(\d{2}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}\.\d{3})\] \d{17} "[^"]+" \S+ @ \d+,\d+,\d+\.$/';
+
+    public const string FIELDS = '/^\[\d{2}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}\.\d{3}\] (?<steamid>\d{17}) "(?<player>[^"]+)" (?<command>\S+) @ (?<x>\d+),(?<y>\d+),(?<z>\d+)\.$/';
+}