refactor(character): 重构角色动作与动画系统

- 移除自动回退动作生成逻辑，改为严格检查动作定义
- 增加动作资源缺失时的详细错误报告机制
- 统一输入事件处理接口，优化角色对象生命周期管理
- 改进动画标签管理，移除隐式回退逻辑
- 增强状态机对无效动作的处理能力

Game/src/character/CharacterAnimation.cpp

@@ -3,6 +3,7 @@
 #include <SDL2/SDL.h>
 #include <array>
 #include <cstdio>
+#include <sstream>
 
 namespace frostbite2D {
 namespace {
@@ -51,12 +52,6 @@ bool CharacterAnimation::Init(CharacterObject* parent,
     return false;
   }
 
-  if (actionAnimations_.count("rest") > 0) {
-    SetAction("rest");
-  } else {
-    SetAction(actionAnimations_.begin()->first);
-  }
-
   return true;
 }
 
@@ -129,13 +124,37 @@ void CharacterAnimation::CreateAnimationBySlot(
   }
 }
 
-void CharacterAnimation::SetAction(const std::string& actionName) {
+std::string CharacterAnimation::DescribeAvailableActions() const {
+  if (actionAnimations_.empty()) {
+    return "<none>";
+  }
+
+  std::ostringstream stream;
+  bool first = true;
+  for (const auto& [actionName, animations] : actionAnimations_) {
+    (void)animations;
+    if (!first) {
+      stream << ", ";
+    }
+    stream << actionName;
+    first = false;
+  }
+  return stream.str();
+}
+
+bool CharacterAnimation::SetAction(const std::string& actionName) {
   auto nextIt = actionAnimations_.find(actionName);
   if (nextIt == actionAnimations_.end()) {
-    SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
-                "CharacterAnimation: action %s missing, keep %s", actionName.c_str(),
-                currentActionTag_.c_str());
-    return;
+    if (parent_) {
+      parent_->ReportFatalCharacterError("CharacterAnimation::SetAction",
+                                         "requested animation tag is not loaded",
+                                         std::string(), actionName);
+    } else {
+      SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                   "CharacterAnimation: action %s missing and parent is null",
+                   actionName.c_str());
+    }
+    return false;
   }
 
   if (!currentActionTag_.empty()) {
@@ -154,6 +173,7 @@ void CharacterAnimation::SetAction(const std::string& actionName) {
   }
   currentActionTag_ = actionName;
   SetDirection(direction_);
+  return true;
 }
 
 void CharacterAnimation::SetDirection(int direction) {