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/Authoring/Debug.meta

@@ -0,0 +1,8 @@
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Assets/_Project/Scripts/Authoring/Debug/GymRosterAuthoring.cs

@@ -0,0 +1,49 @@
+using System.Collections.Generic;
+using ProjectM.Simulation;
+using Unity.Entities;
+using UnityEngine;
+
+namespace ProjectM.Authoring
+{
+    /// <summary>
+    /// Bakes the Enemy-test GYM singletons: the <see cref="GymTag"/> mode switch + the <see cref="GymEnemyRoster"/>
+    /// buffer of on-demand-spawnable enemy prefabs (Drowner / Grindylow — the ready skinned prefabs). Place ONE in
+    /// the gym subscene. Each prefab must be a baked ghost (interpolated ownerless enemy, EnemyAuthoring-based). The
+    /// SpawnEnemy dev op instantiates the row whose Kind matches the request.
+    /// </summary>
+    public class GymRosterAuthoring : MonoBehaviour
+    {
+        [System.Serializable]
+        public struct Entry
+        {
+            [Tooltip("Stable kind id (0 = Drowner, 1 = Grindylow).")]
+            public byte Kind;
+            public GameObject Prefab;
+        }
+
+        [Tooltip("On-demand-spawnable enemy prefabs, one row per kind.")]
+        public List<Entry> Enemies = new List<Entry>();
+
+        private class RosterBaker : Baker<GymRosterAuthoring>
+        {
+            public override void Bake(GymRosterAuthoring authoring)
+            {
+                var entity = GetEntity(TransformUsageFlags.None);
+                AddComponent<GymTag>(entity);
+                var buf = AddBuffer<GymEnemyRoster>(entity);
+                if (authoring.Enemies != null)
+                {
+                    foreach (var e in authoring.Enemies)
+                    {
+                        if (e.Prefab == null) continue;
+                        buf.Add(new GymEnemyRoster
+                        {
+                            Kind = e.Kind,
+                            Prefab = GetEntity(e.Prefab, TransformUsageFlags.Dynamic),
+                        });
+                    }
+                }
+            }
+        }
+    }
+}

Assets/_Project/Scripts/Authoring/Debug/GymRosterAuthoring.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: d210e424c43414a4e958efc44c025335

Assets/_Project/Scripts/Client/Debug/DebugCommandSendSystem.cs

@@ -44,6 +44,9 @@ namespace ProjectM.Client
         public static void SetClass(byte classId) => Send(DebugOp.SetClass, classId);
         public static void SetWarrior() => SetClass(ClassTraits.WarriorClass);
         public static void SetRanger() => SetClass(ClassTraits.RangerClass);
+        /// <summary>GYM: spawn enemy KIND (a <see cref="ProjectM.Simulation.GymEnemyKind"/> byte) near the sender, count times.</summary>
+        public static void SpawnEnemy(byte kind, int count = 1) => Send(DebugOp.SpawnEnemy, kind, count);
+
 
         [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
         static void ResetOnEnterPlayMode() => s_Pending.Clear();

Assets/_Project/Scripts/Server/Connection/GoInGameServerSystem.cs

@@ -40,8 +40,14 @@ namespace ProjectM.Server
             // BEFORE the ECB exists — a per-request continue would already have marked the connection in-game.
             // Nothing is consumed; RequireForUpdate re-passes and the request retries next tick (a ≤1-tick window
             // in practice — the director spawns at subscene-stream, before any GoInGame round-trip).
-            if (!SystemAPI.TryGetSingleton<MetaUpgradeCatalog>(out var metaCatalog) || !metaCatalog.Value.IsCreated
-                || !SystemAPI.TryGetSingletonBuffer<MetaTierState>(out var metaRecord, true))
+            // GYM (LANTERN A1): a fresh gym subscene has no CycleDirector, so the base meta-catalog guard would
+            // block spawns forever. GymTag switches to the clean gym path (no meta seeding; a default Spark socket
+            // loadout below instead). The class seeds still apply (harmless: AbilityFireSystem reads sockets).
+            bool isGym = SystemAPI.HasSingleton<GymTag>();
+            MetaUpgradeCatalog metaCatalog = default;
+            DynamicBuffer<MetaTierState> metaRecord = default;
+            if (!isGym && (!SystemAPI.TryGetSingleton<MetaUpgradeCatalog>(out metaCatalog) || !metaCatalog.Value.IsCreated
+                || !SystemAPI.TryGetSingletonBuffer<MetaTierState>(out metaRecord, true)))
             {
                 if (!_warnedMetaBlocked)
                 {
@@ -82,11 +88,22 @@ namespace ProjectM.Server
                 // Expedition redesign: the server-only class anchor the meta systems key on (born-correct meta
                 // seeding at Step 12a + per-class spend at Step 13 resolve the tier record through this).
                 ecb.AddComponent(player, new PlayerClass { ClassId = classId });
+                if (isGym)
+                {
+                    // GYM: default Spark socket loadout on keys 1-4 (AbilityFireSystem reads sockets, not AbilityRef).
+                    // LightZone(9) is defined + dispatch-ready but off the default bar (socket it via a swap).
+                    var gymSockets = ecb.SetBuffer<AbilitySocket>(player);
+                    gymSockets.Add(new AbilitySocket { SparkId = (byte)AbilityId.HookPull });
+                    gymSockets.Add(new AbilitySocket { SparkId = (byte)AbilityId.Blink });
+                    gymSockets.Add(new AbilitySocket { SparkId = (byte)AbilityId.DecoyWisp });
+                    gymSockets.Add(new AbilitySocket { SparkId = (byte)AbilityId.Vortex });
+                }
                 // Step 12a: born-correct PERMANENT meta seeding — replay this class's persisted tiers as
                 // meta-band StatModifiers on the just-instantiated player (same ECB as Instantiate, the
                 // ClassTraits idiom). Skip tier 0 / unknown ids (preserve-don't-crash); CLAMP a saved tier above a
                 // rebalanced MaxTier (D-F5). Class gate via BoonMath.MaskFor (ClassId is the normalized
                 // CharacterId 2/3 — a raw 1<<ClassId would compute bits 2/3 and silently skip everything).
+                if (!isGym)
                 {
                     ref var metaPool = ref metaCatalog.Value.Value;
                     byte classBit = BoonMath.MaskFor(classId);

Assets/_Project/Scripts/Server/Debug/DebugCommandReceiveSystem.cs

@@ -208,6 +208,33 @@ namespace ProjectM.Server
                             }
                         }
                         break;
+                    case DebugOp.SpawnEnemy:
+                        // GYM: spawn a chosen enemy KIND (Drowner/Grindylow) from the baked roster near the sender.
+                        if (sender != Entity.Null && SystemAPI.HasComponent<LocalTransform>(sender)
+                            && SystemAPI.TryGetSingletonEntity<GymTag>(out var gymEntity)
+                            && SystemAPI.HasBuffer<GymEnemyRoster>(gymEntity))
+                        {
+                            var roster = SystemAPI.GetBuffer<GymEnemyRoster>(gymEntity);
+                            Entity enemyPrefab = Entity.Null;
+                            for (int r = 0; r < roster.Length; r++)
+                                if (roster[r].Kind == (byte)cmd.ArgA) { enemyPrefab = roster[r].Prefab; break; }
+                            if (enemyPrefab != Entity.Null)
+                            {
+                                var sPos = SystemAPI.GetComponent<LocalTransform>(sender).Position;
+                                var bakedEnemyLt = state.EntityManager.GetComponentData<LocalTransform>(enemyPrefab);
+                                int spawnCount = math.max(1, cmd.ArgB);
+                                for (int k = 0; k < spawnCount; k++)
+                                {
+                                    float ang = k * 0.7f;
+                                    float3 pos = sPos + new float3(math.cos(ang), 0f, math.sin(ang)) * 5f;
+                                    pos.y = sPos.y;
+                                    var enemy = ecb.Instantiate(enemyPrefab);
+                                    ecb.SetComponent(enemy, bakedEnemyLt.WithPosition(pos));
+                                    ecb.AddComponent(enemy, new RegionTag { Region = RegionId.Base });
+                                }
+                            }
+                        }
+                        break;
                 }
 
                 ecb.DestroyEntity(reqEntity);

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;
     }
 }

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

@@ -0,0 +1,35 @@
+using Unity.Entities;
+
+namespace ProjectM.Simulation
+{
+    /// <summary>
+    /// Singleton tag baked into the Enemy-test GYM subscene (see the LANTERN roadmap A1 gym note). Marks the world
+    /// as the gym so <c>GoInGameServerSystem</c> takes the CLEAN gym spawn path — bypassing the base/meta/cycle
+    /// seeding (the gym has no CycleDirector, so the meta-catalog spawn guard must not block it) and seeding a
+    /// default Spark socket loadout instead. Purely a mode switch; the gym never runs the base siege/economy.
+    /// </summary>
+    public struct GymTag : IComponentData { }
+
+    /// <summary>
+    /// Baked gym enemy roster — one row per on-demand-spawnable enemy KIND (buffer index is arbitrary; match on
+    /// <see cref="Kind"/>). <c>DebugCommandReceiveSystem</c>'s SpawnEnemy op instantiates the row whose Kind ==
+    /// ArgA near the requesting player. Entity refs can't live in a blob, so this is a companion buffer on the
+    /// gym-roster entity (the <see cref="AbilityPrefabElement"/> idiom). Server-read only.
+    /// </summary>
+    [InternalBufferCapacity(4)]
+    public struct GymEnemyRoster : IBufferElementData
+    {
+        /// <summary>Stable enemy-kind key (0 = Drowner, 1 = Grindylow; extend as the roster grows).</summary>
+        public byte Kind;
+
+        /// <summary>The baked enemy ghost prefab entity to instantiate for this kind.</summary>
+        public Entity Prefab;
+    }
+
+    /// <summary>Stable kind ids for <see cref="GymEnemyRoster.Kind"/> / the SpawnEnemy op's ArgA.</summary>
+    public static class GymEnemyKind
+    {
+        public const byte Drowner = 0;
+        public const byte Grindylow = 1;
+    }
+}

Assets/_Project/Scripts/Simulation/Debug/GymComponents.cs.meta

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