feat(gameplay): implement entity update packets

Add S2CEntityUpdate to sync entity positions from server to client, including update handling in the client entity manager and server-side AI updates.

src/gameplay/client_entity_manager.cpp

@@ -36,8 +36,23 @@ void ClientEntityManager::handle_entity_create(EntityID id,
     c->transform.position.value = pos;
 }
 
+void ClientEntityManager::handle_entity_update(UpdateInfo& info) {
+    entt::entity e;
+    {
+        cacc a;
+        if (m_entities.find(a, info.id)) {
+            e = a->second;
+        } else {
+            return;
+        }
+    }
+    auto creature = m_registry.try_get<BaseClientCreature>(e);
+    ASSERT(creature);
+    creature->transform.position.value = info.pos;
+}
+
 void ClientEntityManager::receive_entity_create(S2CEntityCreate& s2c) {
-    EntityCreateElement c;
+    EntityCreateElement c{};
     c.id = s2c.id();
     c.name = s2c.name();
     c.pos = {s2c.pos().x(), s2c.pos().y(), s2c.pos().z()};
@@ -48,6 +63,13 @@ void ClientEntityManager::receive_entity_destory(EntityID id) {
     m_tasks.emplace(Command::DESTORY, id);
 }
 
+void ClientEntityManager::receive_entity_update(S2CEntityUpdate& msg) {
+    UpdateInfo e;
+    e.id = msg.id();
+    e.pos = Tools::get_net_pos(msg.pos());
+    m_tasks.emplace(Command::UPDATE, std::move(e));
+}
+
 void ClientEntityManager::destory(EntityID id) {
     auto client = m_world.get_client();
     Arena arena;
@@ -81,6 +103,11 @@ void ClientEntityManager::handle_task() {
             ASSERT(p);
             handle_entity_destory(*p);
         } break;
+        case Command::UPDATE: {
+            auto* p = std::get_if<UpdateInfo>(&pair.second);
+            ASSERT(p);
+            handle_entity_update(*p);
+        }
         }
     }
 }

src/gameplay/network_client.cpp

@@ -156,6 +156,12 @@ asio::awaitable<void> NetworkClient::read_loop() {
                     m_world.entity_manager().receive_entity_destory(msg->id());
                 }
             } break;
+            case std::to_underlying(PacketEnum::S2C_ENTITY_UPDATE): {
+                auto* msg = Arena::Create<S2CEntityUpdate>(&arena);
+                if (decode_packet(*msg, body_data, header)) {
+                    m_world.entity_manager().receive_entity_update(*msg);
+                }
+            } break;
             }
         }
     } catch (const asio::system_error& e) {

src/gameplay/server_entity_manager.cpp

@@ -22,7 +22,10 @@ void ServerEntityManager::init() {
                                         std::move(c), PigTag{});
     });
 }
-void ServerEntityManager::update() { handle_task(); }
+void ServerEntityManager::update() {
+    handle_task();
+    update_ai();
+}
 
 void ServerEntityManager::handle_task() {
     TaskPair pair;

src/proto/world/entity.proto

@@ -21,4 +21,9 @@ message C2SEntityCreateRequest {
     string uuid = 1;
     string name = 2;
     Vec3 pos = 3;
+}
+
+message S2CEntityUpdate {
+    uint64 id = 1;
+    Vec3 pos = 2;
 }