Known-structures memory + bigger map: fix the East re-founding loop

Root cause of the homeless East: FoundOwnShelter searched all buildings by
proximity (within 30 units), so a lone selfish builder who wandered off to
gather wood for the walls came back, missed their own foundation, and
founded a NEW one - 5,900+ abandoned foundations per run, none finished.

Fix (per the exploration architecture): structures are known like resource
nodes. NPCs gain a KnownStructures set; a builder registers the home they
lay and returns to it via known-structures memory however far they roamed,
instead of re-founding. Children inherit their family's known buildings.
Result: 5,953 -> 31 founding events, East now houses itself with COMPLETED
homes and is the best-fed town (0.84), still lowest-knowledge/highest-debris
as selfishness should be.

Also expanded the world 768 -> 1152 with towns pushed to wider cardinal
points and resources scaled to area, giving the four cultures more room and
less accidental center overlap. Full 240-day four-town run in 189s.

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

scripts/GameManager.cs

@@ -29,10 +29,10 @@ public partial class GameManager : Node2D
     public IReadOnlyList<TownDef> Towns => _towns;
     private readonly List<TownDef> _towns = new()
     {
-        new("North", new Vector2(384f, 130f), SoulType.Generational),
-        new("South", new Vector2(384f, 638f), SoulType.Nature),
-        new("West",  new Vector2(130f, 384f), SoulType.Materialist),
-        new("East",  new Vector2(638f, 384f), SoulType.Selfish),
+        new("North", new Vector2(576f, 190f),  SoulType.Generational),
+        new("South", new Vector2(576f, 962f),  SoulType.Nature),
+        new("West",  new Vector2(190f, 576f),  SoulType.Materialist),
+        new("East",  new Vector2(962f, 576f),  SoulType.Selfish),
     };
 
     private static SoulProfile ProfileFor(SoulType t) => t switch
@@ -324,6 +324,10 @@ public partial class GameManager : Node2D
             // passed down like everything else a generation hands forward.
             foreach (var node in a.KnownNodes) child.KnownNodes.Add(node);
             foreach (var node in b.KnownNodes) child.KnownNodes.Add(node);
+            // A child also inherits the family's known buildings — the homes
+            // and stores of the people who raised them.
+            foreach (var s in a.KnownStructures) child.KnownStructures.Add(s);
+            foreach (var s in b.KnownStructures) child.KnownStructures.Add(s);
             newborns.Add(child);
             BirthsToday++;
             pop[a.HomeTown] = (int)townPop + 1;   // count the newborn toward capacity