Soul layer: imprints, warmth echoes, and consequences

Ports the Unity POC soul systems into the sim:
- Warmth echoes: villagers remember who fed them (+0.15) and who turned
  them away (-0.25). Ask-for-food targeting runs on memory, not
  omniscience; the remembered-cold are not asked. Echoes fade daily.
- Refusing the hungry while holding food marks the refuser (others-regard
  debris) and is logged; empty-handed is not refusal.
- Harvesting below the 50% commons line marks the taker per unit taken.
- Soul-to-soul atmospheric pressure (SoulFieldSystem port): encased souls
  darken nearby atmospheres, clear souls lighten them.
- Debris costs biologically: nourishment drains faster and meals restore
  less as the soul encases.
- Instrumentation: avg_debris + refusals in daily stats; per-villager
  nourish/health/debris; refusals in the contact log; map dots dim with
  encasement.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

scripts/NPC.cs

@@ -52,6 +52,26 @@ public class Npc
     /// souls honor the 50% commons floor; selfish souls strip to ~15%.</summary>
     public float HarvestSeekFloor => Mathf.Max(0.05f, Soul.Sustainability * 0.5f) + 0.05f;
 
+    // --- Social memory: warmth echoes (Unity POC port) --------------------
+    // Not knowledge — feeling. A villager doesn't know who is generous;
+    // they remember who fed them and who turned them away.
+
+    private readonly Dictionary<string, float> _echoes = new();
+
+    public float GetWarmth(string name) => _echoes.TryGetValue(name, out float w) ? w : 0f;
+
+    public void RecordEcho(string name, float delta) =>
+        _echoes[name] = Mathf.Clamp(GetWarmth(name) + delta, -1f, 1f);
+
+    /// <summary>Echoes drift back toward neutral — called once per day.
+    /// A single contact fades in weeks; a pattern of contact holds.</summary>
+    public void FadeEchoes(float amount)
+    {
+        var keys = new List<string>(_echoes.Keys);
+        foreach (var key in keys)
+            _echoes[key] = Mathf.MoveToward(_echoes[key], 0f, amount);
+    }
+
     /// <summary>Ticks spent in each state since the last daily snapshot —
     /// the raw material of emergent roles: what a person mostly does is
     /// who they are becoming. Indexed by (int)NpcState.</summary>
@@ -107,13 +127,16 @@ public class Npc
         }
 
         // Metabolism: nourishment drains slowly; eat from the pack when hungry.
-        // This is the per-capita demand that keeps the economy from saturating.
-        Nourishment -= 0.35f / 1440f;
+        // The soul layer bites here (Unity POC rule): a burdened soul wears
+        // faster, and the same meal gives it less. Debris is not a scoreboard —
+        // it is a way of being that costs.
+        float debris = Imprint.Total;
+        Nourishment -= (0.35f / 1440f) * (1f + debris);
         if (Nourishment < 0.7f &&
             Inventory.TryGetValue(MaterialKind.Food, out float food) && food >= 1f)
         {
             Inventory[MaterialKind.Food] = food - 1f;
-            Nourishment = Mathf.Min(1f, Nourishment + 0.25f);
+            Nourishment = Mathf.Min(1f, Nourishment + 0.25f * (1f - debris * 0.5f));
         }
         if (Nourishment <= 0.05f) Health = Mathf.Max(0f, Health - 0.01f);
         Nourishment = Mathf.Clamp(Nourishment, 0f, 1f);
@@ -244,8 +267,7 @@ public class Npc
             MoveToward(_giftSource.Position);
             if (Position.DistanceTo(_giftSource.Position) < ArriveDist)
             {
-                if (TradeSystem.CanTrade(_giftSource, this, out var mat))
-                    TradeSystem.Execute(_giftSource, this, mat);
+                TradeSystem.RequestGift(_giftSource, this);
                 _giftSource = null;
             }
             return;
@@ -280,15 +302,18 @@ public class Npc
                         return;
                     }
 
-                float bestDist = float.MaxValue;
+                // Ask whoever might help — chosen by memory, not omniscience.
+                // The warm are asked first; the remembered-cold aren't asked
+                // at all. A stranger gets the benefit of the doubt once.
+                float bestScore = float.MinValue;
                 foreach (var other in gm.Npcs)
                 {
                     if (other == this) continue;
-                    // Everyone knows better than to ask the ungenerous.
-                    if (other.Soul.Generosity < 0.3f) continue;
+                    float warmth = GetWarmth(other.Name);
+                    if (warmth < -0.3f) continue;
                     if (!other.Inventory.TryGetValue(MaterialKind.Food, out float f) || f <= 3f) continue;
-                    float d = Position.DistanceSquaredTo(other.Position);
-                    if (d < bestDist) { bestDist = d; _giftSource = other; }
+                    float score = warmth * 40f - Position.DistanceTo(other.Position);
+                    if (score > bestScore) { bestScore = score; _giftSource = other; }
                 }
                 if (_giftSource != null) return;
             }
@@ -308,7 +333,7 @@ public class Npc
         else
         {
             Activity = $"harvesting {_targetNode.Kind.ToString().ToLower()}";
-            float taken = world.Harvest(_targetNode, requested: 2f, Soul);
+            float taken = world.Harvest(_targetNode, requested: 2f, this);
             if (taken <= 0f) { _targetNode = null; return; }  // node at its floor — re-seek
             Inventory.TryGetValue(_targetNode.Kind, out float have);
             Inventory[_targetNode.Kind] = have + taken;