fix: 调整游戏地平线并修复UI元素位置与显示问题

- 将游戏地平线从100调整为0，修正游戏世界坐标基准
- 修复地图中多个物体的Y轴位置偏移问题
- 调整hnode.prefab中按钮尺寸、字体大小和布局边距
- 修复role_controller.prefab中控制面板的激活状态和位置
- 移除prefab中多余的instance和targetOverrides字段

assets/resources/game/map/map_rpg.prefab

@@ -856,7 +856,7 @@
     "_lpos": {
       "__type__": "cc.Vec3",
       "x": 0,
-      "y": 53.287,
+      "y": -46.713,
       "z": 0
     },
     "_lrot": {
@@ -992,7 +992,7 @@
     "_lpos": {
       "__type__": "cc.Vec3",
       "x": 0,
-      "y": 56.08,
+      "y": -43.92,
       "z": 0
     },
     "_lrot": {
@@ -1128,7 +1128,7 @@
     "_lpos": {
       "__type__": "cc.Vec3",
       "x": 0,
-      "y": -363.417,
+      "y": -463.417,
       "z": 0
     },
     "_lrot": {
@@ -1267,7 +1267,7 @@
     "_lpos": {
       "__type__": "cc.Vec3",
       "x": 0,
-      "y": -28,
+      "y": -128,
       "z": 0
     },
     "_lrot": {
@@ -1383,7 +1383,7 @@
     "_left": 0,
     "_right": 0,
     "_top": 0,
-    "_bottom": 22,
+    "_bottom": -78,
     "_horizontalCenter": 0,
     "_verticalCenter": 0,
     "_isAbsLeft": true,