Optimize pack file loading

- Add thread-local ZSTD decompression context reuse
- Integrate BufferPool for temporary buffers
- PackManager auto-uses BufferPool for all GetFile calls
- Thread-safe pack loading with mutex

src/PackLib/PackManager.h

@@ -1,26 +1,34 @@
 #pragma once
 #include <unordered_map>
+#include <mutex>
 
 #include "EterBase/Singleton.h"
 #include "Pack.h"
 
+class CBufferPool;
+
 class CPackManager : public CSingleton<CPackManager>
 {
 public:
-	CPackManager() = default;
-	virtual ~CPackManager() = default;
+	CPackManager();
+	virtual ~CPackManager();
 
 	bool AddPack(const std::string& path);
 	bool GetFile(std::string_view path, TPackFile& result);
+	bool GetFileWithPool(std::string_view path, TPackFile& result, CBufferPool* pPool);
 	bool IsExist(std::string_view path) const;
 
 	void SetPackLoadMode() { m_load_from_pack = true; }
 	void SetFileLoadMode() { m_load_from_pack = false; }
 
+	CBufferPool* GetBufferPool() { return m_pBufferPool; }
+
 private:
 	void NormalizePath(std::string_view in, std::string& out) const;
 
 private:
 	bool m_load_from_pack = true;
 	TPackFileMap m_entries;
+	CBufferPool* m_pBufferPool;
+	mutable std::mutex m_mutex;  // Thread safety for parallel pack loading
 };