feat(@projects/@magic-civilization): ✨ add race/resource filtering to melee unit selection

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

src/simulator/crates/mc-ai/src/tactical/production.rs

@@ -202,7 +202,12 @@ fn pick_for_city(
     // Tier-progression unit selection (p0-39). Highest-tier buildable military
     // unit for this player; falls back to `warrior` when the catalog is empty
     // (fixtures predating p0-39) or no higher-tier gate is met.
-    let melee_id = pick_best_melee(&player.researched_techs, unit_catalog).unwrap_or(ids::WARRIOR);
+    let melee_id = pick_best_melee(
+        &player.researched_techs,
+        player.race_id.as_deref(),
+        &player.strategic_resources,
+        unit_catalog,
+    ).unwrap_or(ids::WARRIOR);
     let early_mil_floor = if turn <= EARLY_MIL_FLOOR_CUTOFF_TURN {
         EARLY_MIL_FLOOR
     } else {

src/simulator/crates/mc-ai/src/tactical/state.rs

@@ -94,6 +94,18 @@ pub struct TacticalPlayerState {
     /// Diplomatic relations per opponent slot. `<0` war, `0` peace, `>0`
     /// friend. Self-slot is 0.
     pub relations: Vec<i8>,
+    /// Race id (e.g. `"dwarf"`, `"human"`). `None` for fixtures predating
+    /// race-gated unit selection. Consumed by
+    /// `tactical::production::pick_best_melee` to filter units whose
+    /// `race_required` doesn't match.
+    #[serde(default)]
+    pub race_id: Option<String>,
+    /// Strategic resource ids the player currently controls (tiles they own
+    /// that provide `iron_ore`, `horses`, etc.). Consumed by
+    /// `tactical::production::pick_best_melee` to filter units whose
+    /// `requires_resource` isn't available.
+    #[serde(default)]
+    pub strategic_resources: Vec<String>,
     /// Clan personality axes on the `1..=10` scale (neutral = 5). Consumed by
     /// `tactical::thresholds` for personality-emergent posture / retreat /
     /// chase / siege thresholds (p0-37). Empty map = baseline (axis=5 for
@@ -152,6 +164,18 @@ pub struct TacticalUnitSpec {
     /// Unit-type classification mirroring `units/*.json::unit_type`:
     /// `"military"` | `"worker"` | `"founder"` | `"scout"` | …
     pub unit_type: String,
+    /// Strategic resource gate — unit buildable only when the player owns at
+    /// least one tile providing this resource id (e.g. `"iron_ore"` for
+    /// cavalry). `None` means no resource requirement. Filtered by
+    /// `tactical::production::pick_best_melee` to avoid queueing units the
+    /// engine's strategic-gate check will reject.
+    #[serde(default)]
+    pub requires_resource: Option<String>,
+    /// Race gate — unit buildable only when the player's race matches this id
+    /// (e.g. `"dwarf"` for berserker / ironwarden / forge_titan). `None`
+    /// means no race restriction.
+    #[serde(default)]
+    pub race_required: Option<String>,
 }
 
 /// A city.