fix(hero): 修正治疗特效的资源路径与动画参数

1. 将治疗特效的资源路径从heathed改为end/heal
2. 调整治疗动画的采样率和时长以优化表现
3. 新增攻击力提升、冷却缩减的技能结束特效预制体

assets/resources/game/skill/anm/buff/heal.anim

@@ -7,11 +7,11 @@
       "embeddedPlayerGroups": []
     },
     "_native": "",
-    "sample": 18,
+    "sample": 14,
     "speed": 1,
     "wrapMode": 1,
     "enableTrsBlending": false,
-    "_duration": 0.3888888888888889,
+    "_duration": 0.5,
     "_hash": 500763545,
     "_tracks": [
       {
@@ -69,12 +69,12 @@
     "__type__": "cc.ObjectCurve",
     "_times": [
       0,
-      0.05555555555555555,
-      0.1111111111111111,
-      0.16666666666666666,
-      0.2222222222222222,
-      0.2777777777777778,
-      0.3333333333333333
+      0.07142857142857142,
+      0.14285714285714285,
+      0.21428571428571427,
+      0.2857142857142857,
+      0.35714285714285715,
+      0.42857142857142855
     ],
     "_values": [
       {