Slice 3: Expedition Combat Spine — epoch-seeded zone waves (DR-040)

Reactivate the dormant Expedition region as a procedural combat venue.
v1 loop: walk the gate -> fight an epoch-seeded enemy wave in the
expedition -> clear -> return -> flat Ore reward (once per epoch) ->
escalated retaliation base siege.

- New sim types: ZoneEnemyTag, ZoneEnemyDirector (+ ZoneEnemyPrefab
  buffer), ZoneEnemyState, ZoneEnemyMath (grunt->charger composition
  by epoch). ZoneEnemyDirectorSystem (server, Burst): drip-spawns the
  wave at a deterministic ring under a MaxAlive cap while a player is
  out and the base is Calm; marks ClearedThisEpoch on a real clear.
  [UpdateAfter(ExpeditionFieldSystem)] only (avoids a sort cycle).
- BLOCKER 1: EnemyAISystem region-filters target selection (player +
  structure snapshots gain parallel region lists; no base structures /
  no Core fallback for expedition husks).
- BLOCKER 3: WaveSystem, ThreatDirectorSystem timeout cull, and
  CyclePhaseSystem DefendCleared + Core-breach cull all count/cull
  RegionTag{Base} husks only (the breach cull was caught region-blind
  by the post-impl review: a base breach wiped the live expedition
  wave and spuriously paid the reward).
- BLOCKER 4: reward de-duped via CycleRuntime.LastRewardedEpoch +
  ClearedThisEpoch; ExpeditionGateSystem deposits RewardOre once/epoch.
- ExpeditionFieldSystem teardown also culls zone enemies + region-
  guards the clutter loop. Subscene wired with the director + roster.

368/368 EditMode green + clean netcode Play smoke. Docs: DR-040 ->
built, session log, CLAUDE.md cross-region tag-reaudit rule.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/_Project/Scripts/Server/Combat/WaveSystem.cs

@@ -23,7 +23,6 @@ namespace ProjectM.Server
     [UpdateInGroup(typeof(SimulationSystemGroup))]
     public partial struct WaveSystem : ISystem
     {
-        EntityQuery m_AliveHusks;
 
         [BurstCompile]
         public void OnCreate(ref SystemState state)
@@ -31,7 +30,6 @@ namespace ProjectM.Server
             state.RequireForUpdate<WaveDirector>();
             state.RequireForUpdate<WaveState>();
             state.RequireForUpdate<NetworkTime>();
-            m_AliveHusks = state.GetEntityQuery(ComponentType.ReadOnly<EnemyTag>());
         }
 
         [BurstCompile]
@@ -100,11 +98,19 @@ namespace ProjectM.Server
                         wave.NextActionTick = TickUtil.NonZero(now + (uint)math.max(1, director.SpawnIntervalTicks));
                     }
                 }
-                else if (m_AliveHusks.CalculateEntityCount() == 0)
+                else
                 {
-                    // Wave cleared: calm before the next.
-                    wave.Phase = WavePhase.Lull;
-                    wave.NextActionTick = TickUtil.NonZero(now + (uint)math.max(1, director.LullTicks));
+                    // Wave fully spawned: cleared only when no BASE husk remains. Expedition zone enemies are also
+                    // EnemyTag but RegionTag{Expedition}; they must NOT hold the base siege open (DR-040 BLOCKER 3).
+                    int baseHusks = 0;
+                    foreach (var hr in SystemAPI.Query<RefRO<RegionTag>>().WithAll<EnemyTag>())
+                        if (hr.ValueRO.Region == RegionId.Base) baseHusks++;
+                    if (baseHusks == 0)
+                    {
+                        // Wave cleared: calm before the next.
+                        wave.Phase = WavePhase.Lull;
+                        wave.NextActionTick = TickUtil.NonZero(now + (uint)math.max(1, director.LullTicks));
+                    }
                 }
             }