Tests: EB-1 structure damage/death, fortress targeting, persistence v3

10 new EditMode tests (312 total, all green): HealthApplyDamage destroys a Destructible at 0 + a wounded structure survives clamped; PickWeightedNearest x5 (player-only, structure-preferred-by-weight, player-in-the-way wins, raze undefended base, no targets); persistence (StructureSave.HP round-trip + writes v3, v2 in the load floor, SaveApply.ToPending maps the wounded HP - the staging-copy bug the pre-code review caught); + the StructureAggroWeight default pin. See DR-032.

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

Assets/_Project/Tests/EditMode/EnemyAIMathTests.cs

@@ -1,6 +1,7 @@
 using NUnit.Framework;
 using ProjectM.Simulation;
 using Unity.Mathematics;
+using Unity.Collections;
 
 namespace ProjectM.Tests
 {
@@ -111,5 +112,63 @@ namespace ProjectM.Tests
             Assert.AreEqual(v.x, slid.x, Eps);
             Assert.AreEqual(v.z, slid.z, Eps);
         }
+        // ---- EB-1 fortress aggro: PickWeightedNearest ----
+
+        [Test]
+        public void PickWeightedNearest_NoStructures_PicksNearestPlayer()
+        {
+            using var players = new NativeList<float3>(Allocator.Temp);
+            using var structs = new NativeList<float3>(Allocator.Temp);
+            players.Add(new float3(10, 0, 0));
+            players.Add(new float3(3, 0, 0));
+            EnemyAIMath.PickWeightedNearest(float3.zero, players, structs, 0.7f, out bool isStruct, out int idx);
+            Assert.IsFalse(isStruct);
+            Assert.AreEqual(1, idx, "nearest player is index 1 (dist 3)");
+        }
+
+        [Test]
+        public void PickWeightedNearest_PrefersStructure_WhenWeightShrinksItsDistance()
+        {
+            using var players = new NativeList<float3>(Allocator.Temp);
+            using var structs = new NativeList<float3>(Allocator.Temp);
+            players.Add(new float3(8, 0, 0));   // effective 8
+            structs.Add(new float3(10, 0, 0));  // 10 * weight 0.5 = effective 5 < 8
+            EnemyAIMath.PickWeightedNearest(float3.zero, players, structs, 0.5f, out bool isStruct, out int idx);
+            Assert.IsTrue(isStruct, "a weighted structure (10*0.5=5) beats a player at 8 -> Husks push for structures");
+            Assert.AreEqual(0, idx);
+        }
+
+        [Test]
+        public void PickWeightedNearest_PlayerInTheWay_WinsOverWeightedStructure()
+        {
+            using var players = new NativeList<float3>(Allocator.Temp);
+            using var structs = new NativeList<float3>(Allocator.Temp);
+            players.Add(new float3(2, 0, 0));   // a player right in the way (dist 2)
+            structs.Add(new float3(10, 0, 0));  // 10 * 0.7 = effective 7 > 2
+            EnemyAIMath.PickWeightedNearest(float3.zero, players, structs, 0.7f, out bool isStruct, out int idx);
+            Assert.IsFalse(isStruct, "a player closer than the weighted structure distance wins (attack the one in the way)");
+            Assert.AreEqual(0, idx);
+        }
+
+        [Test]
+        public void PickWeightedNearest_OnlyStructures_RazesTheUndefendedBase()
+        {
+            using var players = new NativeList<float3>(Allocator.Temp);
+            using var structs = new NativeList<float3>(Allocator.Temp);
+            structs.Add(new float3(0, 0, 12));
+            EnemyAIMath.PickWeightedNearest(float3.zero, players, structs, 0.7f, out bool isStruct, out int idx);
+            Assert.IsTrue(isStruct, "with no players, a Husk targets a structure (razes the undefended base)");
+            Assert.AreEqual(0, idx);
+        }
+
+        [Test]
+        public void PickWeightedNearest_NoTargets_ReturnsMinusOne()
+        {
+            using var players = new NativeList<float3>(Allocator.Temp);
+            using var structs = new NativeList<float3>(Allocator.Temp);
+            EnemyAIMath.PickWeightedNearest(float3.zero, players, structs, 0.7f, out bool isStruct, out int idx);
+            Assert.AreEqual(-1, idx);
+        }
+
     }
 }