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/Debug/TuningConfig.cs

@@ -46,6 +46,10 @@ namespace ProjectM.Simulation
         public float MeleeFinisherMult;
         public float MeleeComboLength;
 
+        // EB-1 fortress aggro: a <1 multiplier on a Husk's SQUARED distance to a structure (so structures are
+        // preferred targets); a closer player 'in the way' still wins. Read server-side by EnemyAISystem.
+        public float StructureAggroWeight;
+
         /// <summary>The baked feel defaults == the pre-MC-0 consts. Single source of truth for the fallback path.</summary>
         public static TuningConfig Defaults() => new TuningConfig
         {
@@ -68,6 +72,7 @@ namespace ProjectM.Simulation
             MeleeKnockbackSpeed = 6f,
             MeleeFinisherMult = 1.8f,            // finisher (last hit) scales dmg/range/recover/knockback
             MeleeComboLength = 3f,               // light, light, finisher
+            StructureAggroWeight = 0.7f,           // EB-1: <1 prefers structures (fortress aggro); live-tunable
         };
 
         /// <summary>Clamp a knob to its safe floor: tick knobs &gt;= 1, value knobs &gt;= 0. Used by every write path
@@ -86,6 +91,7 @@ namespace ProjectM.Simulation
                 case TuningKnob.MeleeSwingMoveScale:
                 case TuningKnob.MeleeKnockbackSpeed:
                 case TuningKnob.MeleeFinisherMult:
+                case TuningKnob.StructureAggroWeight:
                     return math.max(0f, value);
                 // tick knobs: >= 1 (a 0 tick count is degenerate; a 0 i-frame window divides-by-zero in DashSystem)
                 default:
@@ -118,6 +124,7 @@ namespace ProjectM.Simulation
                 case TuningKnob.MeleeKnockbackSpeed: c.MeleeKnockbackSpeed = value; break;
                 case TuningKnob.MeleeFinisherMult: c.MeleeFinisherMult = value; break;
                 case TuningKnob.MeleeComboLength: c.MeleeComboLength = value; break;
+                case TuningKnob.StructureAggroWeight: c.StructureAggroWeight = value; break;
                 // unknown index -> no-op (matches the no-default switch convention in DebugCommandReceiveSystem)
             }
         }
@@ -146,6 +153,7 @@ namespace ProjectM.Simulation
                 case TuningKnob.MeleeKnockbackSpeed: return c.MeleeKnockbackSpeed;
                 case TuningKnob.MeleeFinisherMult: return c.MeleeFinisherMult;
                 case TuningKnob.MeleeComboLength: return c.MeleeComboLength;
+                case TuningKnob.StructureAggroWeight: return c.StructureAggroWeight;
                 default: return 0f;
             }
         }
@@ -172,6 +180,7 @@ namespace ProjectM.Simulation
             MeleeKnockbackSpeed = c.MeleeKnockbackSpeed,
             MeleeFinisherMult = c.MeleeFinisherMult,
             MeleeComboLength = c.MeleeComboLength,
+            StructureAggroWeight = c.StructureAggroWeight,
         };
 
         /// <summary>Reconstruct the full config from a wire snapshot (FULL state, not a delta).</summary>
@@ -196,6 +205,7 @@ namespace ProjectM.Simulation
             MeleeKnockbackSpeed = r.MeleeKnockbackSpeed,
             MeleeFinisherMult = r.MeleeFinisherMult,
             MeleeComboLength = r.MeleeComboLength,
+            StructureAggroWeight = r.StructureAggroWeight,
         };
     }
 
@@ -221,9 +231,10 @@ namespace ProjectM.Simulation
         public const byte MeleeKnockbackSpeed = 16;
         public const byte MeleeFinisherMult = 17;
         public const byte MeleeComboLength = 18;
+        public const byte StructureAggroWeight = 19;
 
         /// <summary>Knob count (overlay iteration bound).</summary>
-        public const byte Count = 19;
+        public const byte Count = 20;
     }
 
     /// <summary>
@@ -253,5 +264,6 @@ namespace ProjectM.Simulation
         public float MeleeKnockbackSpeed;
         public float MeleeFinisherMult;
         public float MeleeComboLength;
+        public float StructureAggroWeight;
     }
 }