[refactor] refactor model runner capture model (#5230)

### What this PR does / why we need it?
Refactor the `capture_model` method in model_runner to directly reuse
the method from vLLM.

Currently, most of the logic in the capture_model method is similar to
that in the vllm code. Directly using the vllm method can reduce the
maintenance cost of the vllm-ascend code. Modify as follows:
1、refactor capture_model function, directly inheriting community methods
2、refactor initialize_aclgraph_capture function, move to
initialize_attn_backend

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

### How was this patch tested?

- vLLM version: release/v0.13.0
- vLLM main:
ad32e3e19c

Signed-off-by: weiguihua2 <weiguihua2@huawei.com>
Co-authored-by: weijinqian0 <1184188277@qq.com>

tests/ut/attention/test_sfa_v1.py

@@ -2,7 +2,6 @@ import sys
 from unittest.mock import MagicMock, patch
 
 import torch
-from vllm.v1.attention.backends.utils import AttentionCGSupport
 
 from tests.ut.base import TestBase
 from vllm_ascend.attention.attention_v1 import AscendAttentionState
@@ -98,7 +97,6 @@ class TestAscendSFAMetadataBuilder(TestBase):
                                            vllm_config=vllm_config,
                                            device=device)
 
-        assert builder.aclgraph_support == AttentionCGSupport.UNIFORM_SINGLE_TOKEN_DECODE
         assert builder.device == device
         assert builder.vllm_config == vllm_config