test(ai-controller): ✅ Add minimal building catalog test data for AI controller JSON parsing validation

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

src/simulator/api-gdext/tests/ai_controller.rs

@@ -73,6 +73,7 @@ fn minimal_tactical_state_json_parses() {
         },
         players: Vec::new(),
         unit_catalog: Vec::new(),
+        building_catalog: Vec::new(),
         difficulty_threshold_mult: 1.0,
     };
     let json = serde_json::to_string(&minimal).expect("serialize");