Fix chest interaction and measure server RTT for latency meter

Chests (and lockboxes, coffers, etc.) failed to open because CMSG_LOOT
was only sent on Classic/Turtle expansions, and only when GO type was
already cached as type 3.  Fix: always send CMSG_LOOT after
CMSG_GAMEOBJ_USE (server silently ignores it for non-lootable objects).
Also broaden CMSG_GAMEOBJ_REPORT_USE to all non-mailbox WotLK GOs.

Latency meter: record pingTimestamp_ in sendPing() and compute RTT in
handlePong(); add toggleable "Show Latency Meter" checkbox in Interface
settings (saved to settings.cfg).

include/game/game_handler.hpp

@@ -1862,6 +1862,7 @@ private:
     float timeSinceLastMoveHeartbeat_ = 0.0f; // Periodic movement heartbeat to keep server position synced
     float moveHeartbeatInterval_ = 0.5f;
     uint32_t lastLatency = 0;                // Last measured latency (milliseconds)
+    std::chrono::steady_clock::time_point pingTimestamp_;  // Time CMSG_PING was sent
 
     // Player GUID and map
     uint64_t playerGuid = 0;

include/ui/game_screen.hpp

@@ -113,6 +113,7 @@ private:
     bool pendingMinimapRotate = false;
     bool pendingMinimapSquare = false;
     bool pendingMinimapNpcDots = false;
+    bool pendingShowLatencyMeter = true;
     bool pendingSeparateBags = true;
     bool pendingAutoLoot = false;
 
@@ -159,6 +160,7 @@ private:
     bool minimapRotate_ = false;
     bool minimapSquare_ = false;
     bool minimapNpcDots_ = false;
+    bool showLatencyMeter_ = true;           // Show server latency indicator
     bool minimapSettingsApplied_ = false;
     bool volumeSettingsApplied_ = false;  // True once saved volume settings applied to audio managers
     bool msaaSettingsApplied_ = false;   // True once saved MSAA setting applied to renderer

src/game/game_handler.cpp

@@ -7642,6 +7642,9 @@ void GameHandler::sendPing() {
     LOG_DEBUG("Sending CMSG_PING (heartbeat)");
     LOG_DEBUG("  Sequence: ", pingSequence);
 
+    // Record send time for RTT measurement
+    pingTimestamp_ = std::chrono::steady_clock::now();
+
     // Build and send ping packet
     auto packet = PingPacket::build(pingSequence, lastLatency);
     socket->send(packet);
@@ -7663,7 +7666,12 @@ void GameHandler::handlePong(network::Packet& packet) {
         return;
     }
 
-    LOG_DEBUG("Heartbeat acknowledged (sequence: ", data.sequence, ")");
+    // Measure round-trip time
+    auto rtt = std::chrono::steady_clock::now() - pingTimestamp_;
+    lastLatency = static_cast<uint32_t>(
+        std::chrono::duration_cast<std::chrono::milliseconds>(rtt).count());
+
+    LOG_DEBUG("Heartbeat acknowledged (sequence: ", data.sequence, ", latency: ", lastLatency, "ms)");
 }
 
 uint32_t GameHandler::nextMovementTimestampMs() {
@@ -15077,10 +15085,12 @@ void GameHandler::performGameObjectInteractionNow(uint64_t guid) {
     // animation/sound and expects the client to request the mail list.
     bool isMailbox = false;
     bool chestLike = false;
-    // Chest-type game objects (type=3): on all expansions, also send CMSG_LOOT so
+    // Always send CMSG_LOOT after CMSG_GAMEOBJ_USE for any gameobject that could be
-    // the server opens the loot response.  Other harvestable/interactive types rely
+    // lootable.  The server silently ignores CMSG_LOOT for non-lootable objects
-    // on the server auto-sending SMSG_LOOT_RESPONSE after CMSG_GAMEOBJ_USE.
+    // (doors, buttons, etc.), so this is safe.  Not sending it is the main reason
-    bool shouldSendLoot = isActiveExpansion("classic") || isActiveExpansion("turtle");
+    // chests fail to open when their GO type is not yet cached or their name doesn't
+    // contain the word "chest" (e.g. lockboxes, coffers, strongboxes, caches).
+    bool shouldSendLoot = true;
     if (entity && entity->getType() == ObjectType::GAMEOBJECT) {
         auto go = std::static_pointer_cast<GameObject>(entity);
         auto* info = getCachedGameObjectInfo(go->getEntry());
@@ -15096,22 +15106,20 @@ void GameHandler::performGameObjectInteractionNow(uint64_t guid) {
             refreshMailList();
         } else if (info && info->type == 3) {
             chestLike = true;
-            // Type-3 chests require CMSG_LOOT on all expansions (AzerothCore WotLK included)
-            shouldSendLoot = true;
-        } else if (turtleMode) {
-            // Turtle compatibility: keep eager loot open behavior.
-            shouldSendLoot = true;
         }
     }
     if (!chestLike && !goName.empty()) {
         std::string lower = goName;
         std::transform(lower.begin(), lower.end(), lower.begin(),
                        [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
-        chestLike = (lower.find("chest") != std::string::npos);
+        chestLike = (lower.find("chest") != std::string::npos ||
-        if (chestLike) shouldSendLoot = true;
+                     lower.find("lockbox") != std::string::npos ||
+                     lower.find("strongbox") != std::string::npos ||
+                     lower.find("coffer") != std::string::npos ||
+                     lower.find("cache") != std::string::npos);
     }
-    // For WotLK chest-like gameobjects, also send CMSG_GAMEOBJ_REPORT_USE.
+    // For WotLK, CMSG_GAMEOBJ_REPORT_USE is required for chests (and is harmless for others).
-    if (!isMailbox && chestLike && isActiveExpansion("wotlk")) {
+    if (!isMailbox && isActiveExpansion("wotlk")) {
         network::Packet reportUse(wireOpcode(Opcode::CMSG_GAMEOBJ_REPORT_USE));
         reportUse.writeUInt64(guid);
         socket->send(reportUse);

src/ui/game_screen.cpp

@@ -8581,6 +8581,7 @@ void GameScreen::renderSettingsWindow() {
         pendingMinimapRotate = minimapRotate_;
         pendingMinimapSquare = minimapSquare_;
         pendingMinimapNpcDots = minimapNpcDots_;
+        pendingShowLatencyMeter = showLatencyMeter_;
         if (renderer) {
             if (auto* minimap = renderer->getMinimap()) {
                 minimap->setRotateWithCamera(minimapRotate_);
@@ -8952,6 +8953,16 @@ void GameScreen::renderSettingsWindow() {
                     }
                 }
 
+                ImGui::Spacing();
+                ImGui::SeparatorText("Network");
+                ImGui::Spacing();
+                if (ImGui::Checkbox("Show Latency Meter", &pendingShowLatencyMeter)) {
+                    showLatencyMeter_ = pendingShowLatencyMeter;
+                    saveSettings();
+                }
+                ImGui::SameLine();
+                ImGui::TextDisabled("(ms indicator near minimap)");
+
                 ImGui::EndChild();
                 ImGui::EndTabItem();
             }
@@ -10080,9 +10091,9 @@ void GameScreen::renderMinimapMarkers(game::GameHandler& gameHandler) {
         break;  // Show at most one queue slot indicator
     }
 
-    // Latency indicator (shown when in world and last latency is known)
+    // Latency indicator (toggleable in Interface settings)
     uint32_t latMs = gameHandler.getLatencyMs();
-    if (latMs > 0 && gameHandler.getState() == game::WorldState::IN_WORLD) {
+    if (showLatencyMeter_ && latMs > 0 && gameHandler.getState() == game::WorldState::IN_WORLD) {
         ImVec4 latColor;
         if      (latMs < 100) latColor = ImVec4(0.3f, 1.0f, 0.3f, 0.8f);   // Green < 100ms
         else if (latMs < 250) latColor = ImVec4(1.0f, 1.0f, 0.3f, 0.8f);   // Yellow < 250ms
@@ -10340,6 +10351,7 @@ void GameScreen::saveSettings() {
     out << "minimap_rotate=" << (pendingMinimapRotate ? 1 : 0) << "\n";
     out << "minimap_square=" << (pendingMinimapSquare ? 1 : 0) << "\n";
     out << "minimap_npc_dots=" << (pendingMinimapNpcDots ? 1 : 0) << "\n";
+    out << "show_latency_meter=" << (pendingShowLatencyMeter ? 1 : 0) << "\n";
     out << "separate_bags=" << (pendingSeparateBags ? 1 : 0) << "\n";
     out << "show_action_bar2=" << (pendingShowActionBar2 ? 1 : 0) << "\n";
     out << "action_bar2_offset_x=" << pendingActionBar2OffsetX << "\n";
@@ -10440,6 +10452,9 @@ void GameScreen::loadSettings() {
                 int v = std::stoi(val);
                 minimapNpcDots_ = (v != 0);
                 pendingMinimapNpcDots = minimapNpcDots_;
+            } else if (key == "show_latency_meter") {
+                showLatencyMeter_ = (std::stoi(val) != 0);
+                pendingShowLatencyMeter = showLatencyMeter_;
             } else if (key == "separate_bags") {
                 pendingSeparateBags = (std::stoi(val) != 0);
                 inventoryScreen.setSeparateBags(pendingSeparateBags);