refactor(heroCard): 重构英雄卡牌系统逻辑与UI布局

1.  重写抽卡逻辑，移除升级卡机制，改为从基础英雄池按权重抽取不重复英雄
2.  优化英雄卡入场、购买、刷新动画，新增按钮触摸反馈效果
3.  调整mission.prefab与cHero.prefab的UI元素位置与布局参数
4.  简化卡牌布局代码，交由prefab的Widget组件自动约束

assets/resources/gui/element/cHero.prefab

@@ -2244,7 +2244,7 @@
     "value": {
       "__type__": "cc.Vec3",
       "x": 0,
-      "y": -95.715,
+      "y": -110.847,
       "z": 0
     }
   },
@@ -2523,14 +2523,14 @@
     "node": {
       "__id__": 1
     },
-    "_enabled": true,
+    "_enabled": false,
     "__prefab": {
       "__id__": 150
     },
-    "_alignFlags": 40,
+    "_alignFlags": 0,
     "_target": null,
-    "_left": 245,
-    "_right": 245,
+    "_left": 310,
+    "_right": 310,
     "_top": 0,
     "_bottom": 0,
     "_horizontalCenter": 0,

assets/resources/gui/element/mission.prefab

@@ -1456,7 +1456,7 @@
     "_lpos": {
       "__type__": "cc.Vec3",
       "x": 306.634,
-      "y": 451.513,
+      "y": 651.253,
       "z": 0
     },
     "_lrot": {
@@ -1975,7 +1975,7 @@
     "_left": -8.317000000000007,
     "_right": -6.6340000000000146,
     "_top": 89.63,
-    "_bottom": 396.513,
+    "_bottom": 596.253,
     "_horizontalCenter": 0,
     "_verticalCenter": 0,
     "_isAbsLeft": true,