chore(mc-core): 🔧 Add post-capture refound suppression logic to combat balance system

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

src/simulator/crates/mc-core/src/combat_balance.rs

@@ -74,6 +74,37 @@ pub struct CombatBalance {
     /// 158 invented per-unit numbers.
     #[serde(default)]
     pub quality_deltas: QualityDeltas,
+    /// p1-29i — post-capture refound suppression. After an empire loses a city
+    /// to capture, it cannot found a *replacement* city for `cooldown_turns`
+    /// turns. This is the capture-stickiness lever the p1-29h Phase-2
+    /// measurement isolated: on the fair gridded duel both empires get pressed
+    /// down to a single city (`per_player_min_cities = [1, 1]`) but neither is
+    /// ever eliminated because the loser instantly refounds, so 20 captures
+    /// produce 0 eliminations (pure churn). A short cooldown gives the attacker
+    /// a window to press the now-undefended capital before the loser rebuilds.
+    /// `cooldown_turns == 0` disables the lever entirely (baseline behaviour).
+    #[serde(default)]
+    pub refound_suppression: RefoundSuppression,
+}
+
+/// p1-29i — post-capture refound-suppression tunables.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+pub struct RefoundSuppression {
+    /// Number of turns after a city *loss* (capture by another player) during
+    /// which the losing empire may not found a replacement city. `0` disables
+    /// the lever (no suppression — preserves pre-p1-29i behaviour).
+    #[serde(default = "default_refound_cooldown_turns")]
+    pub cooldown_turns: u32,
+}
+
+fn default_refound_cooldown_turns() -> u32 {
+    0
+}
+
+impl Default for RefoundSuppression {
+    fn default() -> Self {
+        Self { cooldown_turns: default_refound_cooldown_turns() }
+    }
 }
 
 /// p2-57c — additive combat-stat deltas applied per production-quality band.
@@ -204,6 +235,7 @@ impl Default for CombatBalance {
             low_worker_pool_threshold: default_low_worker_pool_threshold(),
             solo_city_grace: SoloCityGrace::default(),
             quality_deltas: QualityDeltas::default(),
+            refound_suppression: RefoundSuppression::default(),
         }
     }
 }

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

@@ -37,7 +37,8 @@ pub mod worker;
 pub use building::{BuildingEntity, Placement};
 pub use city_action::{CityAction, CityId};
 pub use combat_balance::{
-    parse_combat_balance, CombatBalance, QualityDeltas, SoloCityGrace, StatDelta,
+    parse_combat_balance, CombatBalance, QualityDeltas, RefoundSuppression, SoloCityGrace,
+    StatDelta,
 };
 pub use damage_channel::{ChannelDamageBundle, DamageChannel};
 pub use diplomacy::{AgreementType, MechanicKey};