[wip] add nccl allocator and symm memory and enable TP all reduce for nccl symm

[Amir-19]

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @Amir-19.

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[gemini-code-assist]

Code Review

This pull request introduces a custom NCCL allocator for symmetric memory to optimize tensor-parallel all-reduce operations. The changes are well-structured, including new tests for the functionality. However, I've found a couple of critical issues in the new allocator implementation regarding error handling and thread safety that must be addressed. I've also pointed out a couple of high-severity issues related to debug logging that should be cleaned up.