Fix crash in mount dust: add null check for camera pointer

The mount dust code was calling camera->getForward() without checking if
camera was null first, causing a crash that prevented mounting/dismounting.
Added camera null check to the condition.

include/audio/npc_voice_manager.hpp

@@ -0,0 +1,74 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include <unordered_map>
+#include <cstdint>
+#include <random>
+#include <chrono>
+
+namespace wowee {
+namespace pipeline { class AssetManager; }
+
+namespace audio {
+
+struct VoiceSample {
+    std::string path;
+    std::vector<uint8_t> data;
+};
+
+// NPC voice types (based on creature model/gender)
+enum class VoiceType {
+    HUMAN_MALE,
+    HUMAN_FEMALE,
+    DWARF_MALE,
+    DWARF_FEMALE,
+    NIGHTELF_MALE,
+    NIGHTELF_FEMALE,
+    ORC_MALE,
+    ORC_FEMALE,
+    TAUREN_MALE,
+    TAUREN_FEMALE,
+    TROLL_MALE,
+    TROLL_FEMALE,
+    UNDEAD_MALE,
+    UNDEAD_FEMALE,
+    GNOME_MALE,
+    GNOME_FEMALE,
+    GENERIC,  // Fallback
+};
+
+class NpcVoiceManager {
+public:
+    NpcVoiceManager();
+    ~NpcVoiceManager();
+
+    bool initialize(pipeline::AssetManager* assets);
+    void shutdown();
+
+    // Play greeting sound for NPC at given position
+    void playGreeting(uint64_t npcGuid, VoiceType voiceType, const glm::vec3& position);
+
+    void setVolumeScale(float scale) { volumeScale_ = scale; }
+    float getVolumeScale() const { return volumeScale_; }
+
+private:
+    void loadVoiceSounds();
+    bool loadSound(const std::string& path, VoiceSample& sample);
+    VoiceType detectVoiceType(uint32_t creatureEntry) const;
+
+    pipeline::AssetManager* assetManager_ = nullptr;
+    float volumeScale_ = 1.0f;
+
+    // Voice samples grouped by type
+    std::unordered_map<VoiceType, std::vector<VoiceSample>> voiceLibrary_;
+
+    // Cooldown tracking (prevent spam clicking same NPC)
+    std::unordered_map<uint64_t, std::chrono::steady_clock::time_point> lastPlayTime_;
+    static constexpr float GREETING_COOLDOWN = 2.0f;  // seconds
+
+    std::mt19937 rng_;
+};
+
+} // namespace audio
+} // namespace wowee