[Feature] support aclgraph for model runner v2 (#7110)

### What this PR does / why we need it?
This PR aims to support aclgraph for model runner v2, please see RFC
#5208. The PR contains these modifications:
- adapt to newest commit of vllm main branch.
- supply a unified interface of extra forward context for both model
runner v1 and model runner v2.
- implement graph mode for main model. 

### Does this PR introduce _any_ user-facing change?
no

### How was this patch tested?

- vLLM version: v0.16.0
- vLLM main:
4034c3d32e

---------

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

tests/ut/attention/test_mla_cp.py

@@ -449,7 +449,7 @@ class TestAscendMLAImpl(TestBase):
         self.assertEqual(result.shape[1], N)
         self.assertEqual(result.shape[2], self.impl.kv_lora_rank + 1)
 
-    @patch('vllm_ascend.attention.context_parallel.mla_cp.get_forward_context')
+    @patch('vllm_ascend.ascend_forward_context.get_forward_context')
     @patch("torch_npu.npu_fused_infer_attention_score")
     @patch('torch_npu.npu_attention_update')
     @patch_distributed_groups(dcp_size=2, pcp_size=2, needs_mocks=False)