Migrate raw pointers to unique_ptr and fix memory/stability issues

[crayy8]

• Replace raw pointer ownership with unique_ptr throughout the library: RegistryByteBuffer, ValueData, RegistryKey, RegistryValue, RegistryHiveFile, RegistryHiveBuffer, Cell, HBIN, REGFHeader, NKRecord, VKRecord, ValueListRecord
• Remove AutoCellPtrList and AutoHBINPtrList RAII wrappers now that unique_ptr handles lifetime automatically
• Add virtual destructor to BinaryBlock to prevent UB when deleting through base class pointer
• Fix integer overflow in ByteBuffer::read() bounds check via uint64_t cast
• Fix dangling pointer in RejistryException::what() by caching result in mutable member
• Fix RegistryHiveFile::getErrorMessage() to handle FormatMessageA failure
• Fix REGFHeader::getHBINs() to std::move unique_ptr into vector
• Refactor Rejistry test program to exercise both RegistryHiveFile and RegistryHiveBuffer through shared processRegistryHive() function