fix: NPC 자동 선포에서 방랑 유저국을 제외한다

Ref GeneralAI와 같이 level 0 방랑군을 가중 선포 후보에서 제외한다. 정식 유저국과 NPC국은 같은 가중치를 유지하고 후보 및 RNG 순서를 회귀 테스트로 고정한다.

app/game-engine/src/turn/ai/generalAi/nation/diplomacy.ts

@@ -175,7 +175,11 @@ export const do선전포고 = (ai: GeneralAI) => {
     const currentNationId = ai.nation.id;
     const cities = ai.worldRef.listCities();
     const neighbors = ai.worldRef.listNations().filter((nation) => {
-        if (nation.id <= 0 || nation.id === currentNationId) {
+        // Ref getAllNationStaticInfo() also contains level-0 wandering nations,
+        // but automatic declarations explicitly skip them before adjacency and
+        // weighted target selection. A wandering user ruler must not become an
+        // NPC war target merely because its occupied city is adjacent.
+        if (nation.id <= 0 || nation.id === currentNationId || nation.level === 0) {
             return false;
         }
         return isNeighbor(ai.map!, cities, currentNationId, nation.id, true);