Major refactor:
- Add job priority tiers and async wait APIs to IJobScheduler
- Implement priority-based job queues and scheduling logic
- Introduce UnsafeParallelHashMap and refactor UnsafeParallelQueue
- Refactor UnsafeSlotMap to chunked storage for scalability
- Update SlotMap/ConcurrentSlotMap for consistency and perf
- Add new benchmarks and unit tests for parallel collections
- Misc: add MemoryUtility.AlignUp, version bumps, test improvements, bug fixes
Added a TLSF (Two-Level Segregated Fit) memory allocator with O(1) allocation, free, and reallocation in `TLSF.cs`, plus comprehensive unit tests. Introduced a cache-line-padded `SeqLock` synchronization primitive. Refactored vector extension code for conciseness and fixed its usage to `extension(ref ...)`. Updated namespaces, removed unused code, and improved assertion and diagnostics. Updated NuGet dependencies and project files.
