Slice 2 (WIP): class carrier (GoInGameRequest.ClassId) + Warrior cone archetype

The per-player class travels on GoInGameRequest.ClassId (client reads a ClassSelection
singleton); GoInGameServerSystem seeds the class at spawn via ClassTraits (AbilityRef +
permanent trait StatModifiers on a reserved ClassSourceId; CharacterStatsRef stays Default
so the DRG-asymmetry deltas ride the replicated OwnerSendType.All buffer). AbilityFireSystem
gains the aim-directed Cone archetype: cooldown predicted both worlds, server-only cone
damage to living enemies (same-tick, SourceTick-stamped, like the melee cleave). 345/345.

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

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

@@ -42,8 +42,8 @@ namespace ProjectM.Server
                 center = BaseGridMath.PlotCenter(baseAnchor);
             var ecb = new EntityCommandBuffer(Allocator.Temp);
 
-            foreach (var (receive, requestEntity) in
-                     SystemAPI.Query<RefRO<ReceiveRpcCommandRequest>>().WithAll<GoInGameRequest>().WithEntityAccess())
+            foreach (var (receive, goReq, requestEntity) in
+                     SystemAPI.Query<RefRO<ReceiveRpcCommandRequest>, RefRO<GoInGameRequest>>().WithEntityAccess())
             {
                 var connection = receive.ValueRO.SourceConnection;
                 ecb.AddComponent<NetworkStreamInGame>(connection);
@@ -55,6 +55,12 @@ namespace ProjectM.Server
                 ecb.SetComponent(player, new GhostOwner { NetworkId = networkId.Value });
                 // Tag the player into the base region (M6 region/relevancy split).
                 ecb.AddComponent(player, new RegionTag { Region = RegionId.Base });
+                // Slice 2: seed the chosen class on the just-instantiated player. AbilityRef selects the Fire slot
+                // (Warrior = cone / Ranger = projectile); the DRG-asymmetry traits ride permanent StatModifiers
+                // (CharacterStatsRef stays Default -> deltas replicate via the OwnerSendType.All buffer). 0 -> Warrior.
+                byte classId = ClassTraits.Normalize(goReq.ValueRO.ClassId);
+                ecb.SetComponent(player, new AbilityRef { Id = ClassTraits.AbilityFor(classId) });
+                ClassTraits.AppendSeeds(classId, player, ecb);
 
                 // Auto-despawn the player when its owning connection is removed.
                 ecb.AppendToBuffer(connection, new LinkedEntityGroup { Value = player });