EB-1: machines can die - structures get HP, Husks raze them, wounded base persists

Structures (Turret/Wall/Pylon) reuse the combat spine: authoring bakes Health(GhostField)+DamageEvent buffer+a Destructible tag (no HitRadius -> no friendly projectile fire; no EffectiveCharacterStats -> clamp-to-0). HealthApplyDamageSystem destroys a Destructible at 0 (occupancy auto-frees). EnemyAISystem fortress-targets the weighted-nearest of players+structures via the shared EnemyAIMath.PickWeightedNearest (StructureAggroWeight TuningConfig knob, <1 prefers structures, squared factor; snapshot above the early-return so an undefended base is razed). Persistence v3: per-structure HP threaded through 5 sites (SaveData/PendingStructure/scan-guarded/BaseRestore same-ECB born-correct/WorldLauncher via SaveApply.ToPending); SaveService floor-gate [2,3] loads old saves. Loss feedback: proximity-gated StructureFeedbackSystem; CombatFeedbackSystem suppressed for structures. Pre-code review caught the DamageEvent-buffer crash blocker + 8 majors; post-code review clean. See DR-032.

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

Assets/_Project/Scripts/Authoring/Building/StructureAuthoring.cs

@@ -17,6 +17,8 @@ namespace ProjectM.Authoring
         [Tooltip("StructureType byte: 5 = Wall, 6 = Pylon (do NOT use 1-4: Turret + reserved M7 automation).")]
         public byte Kind = StructureType.Wall;
 
+        [Min(1f)] public float MaxHp = 150f;
+
         private class StructureBaker : Baker<StructureAuthoring>
         {
             public override void Bake(StructureAuthoring authoring)
@@ -29,6 +31,12 @@ namespace ProjectM.Authoring
                     NextTick = 0u,
                     LastProcessedTick = 0u,
                 });
+                // EB-1: Wall/Pylon are damageable + destructible AI targets (a wall soaks Husk strikes that would
+                // otherwise hit a turret). DamageEvent buffer MUST exist or an AI strike crashes at ECB playback.
+                // No HitRadius -> ProjectileDamageSystem ignores them (no friendly projectile fire).
+                AddComponent(entity, new Health { Current = authoring.MaxHp, Max = authoring.MaxHp });
+                AddBuffer<DamageEvent>(entity);
+                AddComponent<Destructible>(entity);
             }
         }
     }