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/Simulation/Persistence/SaveApply.cs

@@ -15,5 +15,20 @@ namespace ProjectM.Simulation
             for (int i = 0; i < src.Length; i++)
                 dest.Add(new StorageEntry { ItemId = src[i].ItemId, Count = src[i].Count });
         }
+
+        /// <summary>EB-1: map a serialized <see cref="StructureSave"/> to the staged <see cref="PendingStructure"/>
+        /// (the menu->ServerWorld copy in WorldLauncher). Pure so the field-for-field copy — including the
+        /// easy-to-miss HP — is unit-tested; an omitted field here silently restores every structure at full HP.</summary>
+        public static PendingStructure ToPending(in StructureSave s) => new PendingStructure
+        {
+            Type = s.Type,
+            CellX = s.CellX,
+            CellZ = s.CellZ,
+            Direction = s.Direction,
+            RemainingTicks = s.RemainingTicks,
+            ConveyorResId = s.ConveyorResId,
+            ConveyorCount = s.ConveyorCount,
+            HP = s.HP,
+        };
     }
 }

Assets/_Project/Scripts/Simulation/Persistence/SaveComponents.cs

@@ -37,6 +37,7 @@ namespace ProjectM.Simulation
         public uint RemainingTicks;
         public byte ConveyorResId;
         public int ConveyorCount;
+        public float HP; // EB-1: staged hit points (BaseRestoreSystem restores 0 -> baked Max)
     }
 
     /// <summary>One staged machine I/O row (M7), joined to the <see cref="PendingStructure"/> buffer by index.

Assets/_Project/Scripts/Simulation/Persistence/SaveData.cs

@@ -25,6 +25,7 @@ namespace ProjectM.Simulation
         public uint RemainingTicks;  // production/cooldown ticks left at save time
         public byte ConveyorResId;   // in-flight conveyor item resource (0 = none)
         public int ConveyorCount;
+        public float HP;             // EB-1: hit points at save time (0 from a pre-v3 save -> restored to baked Max)
     }
 
     /// <summary>
@@ -50,7 +51,10 @@ namespace ProjectM.Simulation
     [Serializable]
     public class SaveData
     {
-        public const int CurrentVersion = 2;
+        public const int CurrentVersion = 3; // EB-1: v3 adds StructureSave.HP
+
+        /// <summary>Oldest save schema the loader accepts (additive); a v2 save loads with structures at full HP.</summary>
+        public const int MinLoadableVersion = 2;
 
         public int Version = CurrentVersion;
         public int GoalCharge;

Assets/_Project/Scripts/Simulation/Persistence/SaveService.cs

@@ -23,7 +23,9 @@ namespace ProjectM.Simulation
             {
                 if (!File.Exists(FilePath)) return null;
                 var data = JsonUtility.FromJson<SaveData>(File.ReadAllText(FilePath));
-                if (data == null || data.Version != SaveData.CurrentVersion) return null;
+                // EB-1: additive floor [MinLoadableVersion, CurrentVersion] so OLD v2 saves still load (a missing HP
+                // field 0-defaults and the restore guard maps 0 -> baked Max); v0/v1 garbage is still rejected.
+                if (data == null || data.Version < SaveData.MinLoadableVersion || data.Version > SaveData.CurrentVersion) return null;
                 data.Ledger ??= Array.Empty<LedgerRow>();
                 return data;
             }

Assets/_Project/Scripts/Simulation/Persistence/SaveStructureScan.cs

@@ -35,6 +35,8 @@ namespace ProjectM.Simulation
                     CellX = ps.Cell.x,
                     CellZ = ps.Cell.y,
                     RemainingTicks = ProductionMath.RemainingTicks(ps.NextTick, nowTick),
+                    // EB-1: guarded so automation machines (no Health) don't crash the autosave path (no try/catch).
+                    HP = em.HasComponent<Health>(e) ? em.GetComponentData<Health>(e).Current : 0f,
                 };
 
                 if (em.HasComponent<Conveyor>(e))