implement model runner v2 basic framework (#5051)

### What this PR does / why we need it?
This PR aim to implement model runner v2 basic framework in vllm-ascend,
the e2e function is not guaranteed by this pr.
 
### Does this PR introduce _any_ user-facing change?
use envs.VLLM_USE_V2_MODEL_RUNNER to decide if choose model_runenr_v2.

### How was this patch tested?

- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

---------

Signed-off-by: Ronald1995 <ronaldautomobile@163.com>

vllm_ascend/worker/v2/utils.py

@@ -0,0 +1,33 @@
+from contextlib import contextmanager
+
+import torch
+
+
+@contextmanager
+def torch_cuda_wrapper():
+    ori_event = torch.cuda.Event
+    ori_stream = torch.cuda.Stream
+    ori_default_stream = torch.cuda.default_stream
+    ori_current_stream = torch.cuda.current_stream
+    ori_graph_pool_handle = torch.cuda.graph_pool_handle
+    ori_cuda_graph_cls = torch.cuda.CUDAGraph
+    ori_cuda_graph_func = torch.cuda.graph
+    try:
+        torch.cuda.Event = torch.npu.Event
+        torch.cuda.Stream = torch.npu.Stream
+        torch.cuda.default_stream = torch.npu.default_stream
+        torch.cuda.current_stream = torch.npu.current_stream
+        torch.cuda.graph_pool_handle = torch.npu.graph_pool_handle
+        torch.cuda.CUDAGraph = torch.npu.NpuGraph
+        torch.cuda.graph = torch.npu.graph
+        yield
+    finally:
+        # revert back torch cuda properties, so it will still raise error
+        # to call cuda ops in npu environment.
+        torch.cuda.Event = ori_event
+        torch.cuda.Stream = ori_stream
+        torch.cuda.default_stream = ori_default_stream
+        torch.cuda.current_stream = ori_current_stream
+        torch.cuda.graph_pool_handle = ori_graph_pool_handle
+        torch.cuda.CUDAGraph = ori_cuda_graph_cls
+        torch.cuda.graph = ori_cuda_graph_func