[pipeline]: fix p2p comm, add metadata cache and support llama interleaved pp (#5134)

* test: add more p2p tests

* fix: remove send_forward_recv_forward as p2p op list need to use the same group

* fix: make send and receive atomic

* feat: update P2PComm fn

* feat: add metadata cache in 1f1b

* feat: add metadata cache in interleaved pp

* feat: modify is_xx_stage fn

* revert: add _broadcast_object_list

* feat: add interleaved pp in llama policy

* feat: set NCCL_BUFFSIZE in HybridParallelPlugin