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/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;