Introduce VirtualArena for large, thread-safe virtual memory allocation and FreeList allocator for efficient persistent allocations. Update AllocationManager to support new allocators, add cross-platform virtual memory utilities, and improve thread-safety and performance in existing allocators. Bump version to 1.5.0 and update project configuration.
BREAKING CHANGE: AllocationManager initialization now requires explicit parameters for arena and FreeList capacities. Existing allocator usage may require code changes.