feat(npc): 添加NPC数据加载、动画和对象功能

实现NPC系统的核心功能，包括：
1. 新增NpcDataLoader用于加载NPC索引和配置数据
2. 添加NpcAnimation处理NPC动画显示
3. 创建NpcObject实现NPC交互和显示逻辑
4. 在GameMapTestScene中集成测试NPC功能

Game/src/npc/NpcObject.cpp

@@ -0,0 +1,214 @@
+#include "npc/NpcObject.h"
+#include "common/math/GameMath.h"
+#include <SDL2/SDL.h>
+
+namespace frostbite2D {
+namespace {
+
+constexpr float kNpcNameMarginY = 8.0f;
+constexpr float kNpcNameFallbackTopY = -96.0f;
+const Vec2 kNpcNameOutlineOffsets[] = {
+    Vec2(-1.0f, -1.0f), Vec2(-1.0f, 0.0f), Vec2(-1.0f, 1.0f),
+    Vec2(0.0f, -1.0f),                       Vec2(0.0f, 1.0f),
+    Vec2(1.0f, -1.0f),  Vec2(1.0f, 0.0f),  Vec2(1.0f, 1.0f),
+};
+
+void ConfigureNameTextLabel(RefPtr<TextSprite> label,
+                            const char* name,
+                            const Color& color,
+                            int zOrder) {
+  if (!label) {
+    return;
+  }
+
+  label->SetName(name);
+  label->SetFont("default");
+  label->SetAnchor(0.5f, 1.0f);
+  label->SetTextColor(color);
+  label->SetZOrder(zOrder);
+}
+
+const std::string& EmptyString() {
+  static const std::string kEmpty;
+  return kEmpty;
+}
+
+} // namespace
+
+bool NpcObject::Construction(int npcId) {
+  RemoveAllChildren();
+  npcId_ = -1;
+  direction_ = 1;
+  worldPosition_ = CharacterWorldPosition();
+  config_.reset();
+  animation_ = nullptr;
+  nameOutlineLabels_.fill(nullptr);
+  nameLabel_ = nullptr;
+  interactable_ = true;
+  interacting_ = false;
+
+  auto config = npc::loadNpcConfig(npcId);
+  if (!config) {
+    SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
+                "NpcObject: failed to load npc config %d", npcId);
+    return false;
+  }
+
+  auto animation = MakePtr<NpcAnimation>();
+  if (!animation->Init(*config)) {
+    SDL_LogWarn(SDL_LOG_CATEGORY_APPLICATION,
+                "NpcObject: failed to init npc animation %d", npcId);
+    return false;
+  }
+
+  SDL_Log("NpcObject: npc %d config loaded name=%s fieldName=%s ani=%s",
+          npcId, config->name.c_str(), config->fieldName.c_str(),
+          config->fieldAnimationPath.c_str());
+
+  config_ = *config;
+  npcId_ = npcId;
+  animation_ = animation;
+  AddChild(animation_);
+  EnsureNameLabel();
+
+  SetWorldPosition({});
+  SetDirection(1);
+  RefreshNameLabel();
+  SDL_Log("NpcObject: npc %d construction complete", npcId_);
+  return true;
+}
+
+void NpcObject::SetDirection(int direction) {
+  direction_ = direction >= 0 ? 1 : -1;
+  if (animation_) {
+    animation_->SetDirection(direction_);
+  }
+  RefreshNameLabel();
+}
+
+void NpcObject::SetNpcPosition(const Vec2& pos) {
+  worldPosition_.x = gameMath::RoundWorldCoordinate(pos.x);
+  worldPosition_.y = gameMath::RoundWorldCoordinate(pos.y);
+  SDL_Log("NpcObject: npc %d set ground position to (%d, %d, %d)",
+          npcId_, worldPosition_.x, worldPosition_.y, worldPosition_.z);
+  SyncActorPositionFromWorld();
+}
+
+void NpcObject::SetWorldPosition(const CharacterWorldPosition& pos) {
+  worldPosition_ = pos;
+  SDL_Log("NpcObject: npc %d set world position to (%d, %d, %d)",
+          npcId_, worldPosition_.x, worldPosition_.y, worldPosition_.z);
+  SyncActorPositionFromWorld();
+}
+
+void NpcObject::SetInteractable(bool interactable) {
+  interactable_ = interactable;
+  if (!interactable_) {
+    interacting_ = false;
+  }
+}
+
+void NpcObject::BeginInteract() {
+  if (CanInteract()) {
+    interacting_ = true;
+  }
+}
+
+void NpcObject::EndInteract() {
+  interacting_ = false;
+}
+
+bool NpcObject::CanInteract() const {
+  return interactable_ && config_.has_value();
+}
+
+const std::string& NpcObject::GetName() const {
+  return config_ ? config_->name : EmptyString();
+}
+
+const std::string& NpcObject::GetFieldName() const {
+  return config_ ? config_->fieldName : EmptyString();
+}
+
+const std::string& NpcObject::GetDisplayName() const {
+  const std::string& fieldName = GetFieldName();
+  if (!fieldName.empty()) {
+    return fieldName;
+  }
+  return GetName();
+}
+
+bool NpcObject::IsAnimationFinished() const {
+  return animation_ ? animation_->IsAnimationFinished() : false;
+}
+
+void NpcObject::Update(float deltaTime) {
+  Actor::Update(deltaTime);
+}
+
+void NpcObject::EnsureNameLabel() {
+  if (nameLabel_) {
+    return;
+  }
+
+  for (size_t i = 0; i < nameOutlineLabels_.size(); ++i) {
+    RefPtr<TextSprite> outlineLabel = TextSprite::create();
+    ConfigureNameTextLabel(outlineLabel, "npcNameOutline",
+                           Color(0.0f, 0.0f, 0.0f, 1.0f), 1);
+    nameOutlineLabels_[i] = outlineLabel;
+    AddChild(outlineLabel);
+  }
+
+  nameLabel_ = TextSprite::create();
+  ConfigureNameTextLabel(nameLabel_, "npcName",
+                         Color(1.0f, 0.96f, 0.78f, 1.0f), 2);
+  AddChild(nameLabel_);
+}
+
+void NpcObject::RefreshNameLabel() {
+  if (!nameLabel_) {
+    return;
+  }
+
+  const std::string& displayName = GetDisplayName();
+  bool hasDisplayName = !displayName.empty();
+  nameLabel_->SetVisible(hasDisplayName);
+  for (auto& outlineLabel : nameOutlineLabels_) {
+    if (outlineLabel) {
+      outlineLabel->SetVisible(hasDisplayName);
+    }
+  }
+  if (!hasDisplayName) {
+    return;
+  }
+
+  nameLabel_->SetText(displayName);
+  for (auto& outlineLabel : nameOutlineLabels_) {
+    if (outlineLabel) {
+      outlineLabel->SetText(displayName);
+    }
+  }
+
+  Rect displayBounds;
+  float labelBaseY = kNpcNameFallbackTopY;
+  if (animation_ && animation_->GetDisplayLocalBounds(displayBounds)) {
+    labelBaseY = displayBounds.top() - kNpcNameMarginY;
+  }
+
+  nameLabel_->SetPosition(0.0f, labelBaseY);
+  for (size_t i = 0; i < nameOutlineLabels_.size(); ++i) {
+    if (!nameOutlineLabels_[i]) {
+      continue;
+    }
+
+    const Vec2& offset = kNpcNameOutlineOffsets[i];
+    nameOutlineLabels_[i]->SetPosition(offset.x, labelBaseY + offset.y);
+  }
+}
+
+void NpcObject::SyncActorPositionFromWorld() {
+  SetPosition(worldPosition_.ToScreenPosition());
+  SetZOrder(worldPosition_.y);
+}
+
+} // namespace frostbite2D