LANTERN P1: enemy-test gym tooling — on-demand spawn + GymTag clean-spawn

GymTag + GymEnemyRoster (+ GymRosterAuthoring) bake the gym singletons. New
DebugOp.SpawnEnemy (client SpawnEnemy wrapper + server receive case) spawns a
chosen enemy KIND (Drowner/Grindylow) from the baked roster near the sender —
replacing the wave-roster hack per the roadmap's Enemy-test GYM direction.
GoInGameServerSystem takes a GymTag branch: bypass the meta-catalog spawn guard
(a fresh gym has no CycleDirector) + seed a default Spark loadout on keys 1-4.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Assets/_Project/Scripts/Simulation/Debug/DebugCommandRequest.cs

@@ -68,5 +68,8 @@ namespace ProjectM.Simulation
         /// Strips the old class trait seeds, re-seeds the new ones, swaps the Fire ability, and heals a living
         /// player to the new class's max. Editor-only dev tool (class-switch); 0 / unknown -> Warrior.</summary>
         public const byte SetClass = 13;
+
+        /// <summary>GYM (editor): spawn <see cref="GymEnemyKind"/> ArgA near the sender, ArgB times (default 1). Reads the baked GymEnemyRoster.</summary>
+        public const byte SpawnEnemy = 14;
     }
 }