fix(game): 修复召唤按钮第二次失效和实习生不攻击的Bug

game/towers/TowerBase.ts

@@ -100,7 +100,8 @@ export abstract class TowerBase {
   }
 
   protected findTarget(enemies: EnemyBase[]): EnemyBase | null {
-    const rangePx = this.attackRange * this.cellW
+    // +0.5格容忍量，避免怪物恰好在射程边界时因浮点误差漏判
+    const rangePx = (this.attackRange + 0.5) * this.cellW
     let best: EnemyBase | null = null
     let bestProgress = -1
     for (const e of enemies) {