feat(simulator-specific): ✨ Implement city simulation rules and generation logic in mc-city crate

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

src/simulator/crates/mc-city/src/lib.rs

@@ -33,7 +33,10 @@ pub use yield_fold::{
 };
 
 // Re-export biome-yield types
-pub use biome_yield::{ecology_food_modifier, EcologyYieldsConfig};
+pub use biome_yield::{
+    carrying_capacity_modifier, ecology_food_modifier, BiomeCapacity,
+    BiomeCapacityConfig, EcologyYieldsConfig,
+};
 
 /// Lightweight per-city state used by the bench-grade turn processor.
 ///