fix: 番型互斥从未应用 + FanValue兜底乱给分 + 白名单过滤

Root cause:
1. ApplyFanExclusions定义但从未被调用 → 互斥(清一色⊃缺一门)形同虚设
2. FanValue中 _=>1 兜底 → '缺一门''平胡'等不在DSL的番型也被+1分
3. IdentifyFans返回所有结构模式 → 与DSL配置不一致

修复:
- CheckWin五处IdentifyFans调用后加ApplyFanExclusions
- FanValue去掉_=>1,改为只认DSL配置+硬编码知名番型
- IdentifyFans末尾白名单过滤:只返回DSL或知名番型
- PhaseMachine.GetFanValue同步更新
- ScoreEngine: 不在DSL的番型→0分

RuleEngine/Patterns/MeldsSolver.cs

@@ -43,7 +43,7 @@ public class MeldsSolver
         var sevenPairs = TrySevenPairs(tiles, wildcardCount);
         if (sevenPairs != null)
         {
-            sevenPairs.Fans = IdentifyFans(sevenPairs);
+            sevenPairs.Fans = ApplyFanExclusions(IdentifyFans(sevenPairs));
             return sevenPairs;
         }
 
@@ -51,7 +51,7 @@ public class MeldsSolver
         var thirteen = TryThirteenOrphans(tiles, wildcardCount);
         if (thirteen != null)
         {
-            thirteen.Fans = IdentifyFans(thirteen);
+            thirteen.Fans = ApplyFanExclusions(IdentifyFans(thirteen));
             return thirteen;
         }
 
@@ -59,7 +59,7 @@ public class MeldsSolver
         var allOrphans = TryAllOrphans(tiles, wildcardCount);
         if (allOrphans != null)
         {
-            allOrphans.Fans = IdentifyFans(allOrphans);
+            allOrphans.Fans = ApplyFanExclusions(IdentifyFans(allOrphans));
             return allOrphans;
         }
 
@@ -67,7 +67,7 @@ public class MeldsSolver
         var doubleDragon = TryDoubleDragon(tiles, wildcardCount);
         if (doubleDragon != null)
         {
-            doubleDragon.Fans = IdentifyFans(doubleDragon);
+            doubleDragon.Fans = ApplyFanExclusions(IdentifyFans(doubleDragon));
             return doubleDragon;
         }
 
@@ -82,7 +82,7 @@ public class MeldsSolver
                 if (!IsValid258Pair(result.PairTiles[0], result.PairTiles[1]))
                     return new MeldsResult { IsWin = false };
             }
-            result.Fans = IdentifyFans(result);
+            result.Fans = ApplyFanExclusions(IdentifyFans(result));
             return result;
         }
 
@@ -662,7 +662,11 @@ public class MeldsSolver
         if (melds.Count > 0 && melds.All(m => m.Type == "kezi") && !fans.Contains("对对胡"))
             fans.Add("碰碰和");
 
-        return fans;
+        // Filter: only keep fans that exist in DSL config or are well-known
+        return fans.Where(f => _fanConfig.ContainsKey(f) ||
+            f is "清一色" or "混一色" or "对对胡" or "碰碰和" or "暗七对" or "七对"
+                or "带幺九" or "十三幺" or "字一色" or "断幺九"
+                or "缺一门" or "平胡" or "全大" or "全中" or "全小" or "全双").ToList();
     }
 
     // === 番型互斥应用 ===