refactor(mission): 重构卡牌组件内部状态管理

- 将金币数据从全局 vmdata 移至组件内部私有属性
- 重命名 coins 节点引用为 coins_node 以保持一致性
- 优化卡牌预制体布局，调整名称背景位置和缩放
- 更新数值标签的字体样式和阴影效果
- 修复卡池等级UI更新逻辑，确保正确显示当前等级

assets/resources/gui/ubtns.png.meta

@@ -1,42 +0,0 @@
-{
-  "ver": "1.0.27",
-  "importer": "image",
-  "imported": true,
-  "uuid": "3932da53-985d-4500-8c24-f7c822a4ea46",
-  "files": [
-    ".json",
-    ".png"
-  ],
-  "subMetas": {
-    "6c48a": {
-      "importer": "texture",
-      "uuid": "3932da53-985d-4500-8c24-f7c822a4ea46@6c48a",
-      "displayName": "ubtns",
-      "id": "6c48a",
-      "name": "texture",
-      "userData": {
-        "wrapModeS": "repeat",
-        "wrapModeT": "repeat",
-        "minfilter": "linear",
-        "magfilter": "linear",
-        "mipfilter": "none",
-        "anisotropy": 0,
-        "isUuid": true,
-        "imageUuidOrDatabaseUri": "3932da53-985d-4500-8c24-f7c822a4ea46",
-        "visible": false
-      },
-      "ver": "1.0.22",
-      "imported": true,
-      "files": [
-        ".json"
-      ],
-      "subMetas": {}
-    }
-  },
-  "userData": {
-    "type": "texture",
-    "hasAlpha": true,
-    "fixAlphaTransparencyArtifacts": false,
-    "redirect": "3932da53-985d-4500-8c24-f7c822a4ea46@6c48a"
-  }
-}