[MTP] follow custom deepseek modeling changes to support graph mode (#636)

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### What this PR does / why we need it?

As custom deepseek modeling do some changes to support graph mode in
https://github.com/vllm-project/vllm-ascend/pull/585, so i follow it to
change custom deepseek_mtp modeling.

And some modifications for k>1 were not carried over by the
https://github.com/vllm-project/vllm-ascend/pull/429, now i add it.

In order to better take care of the MTP feature in the vllm-ascend
repository, I added cases related to graph mode(torchair), but i skip it
since torchair can not correctly clean up memory in vllmrunner.

Also i add some case for MTP quantization weights, but test weight is
not ready, so i skip it and i will open it when test quant weights is
ready.

https://github.com/vllm-project/vllm-ascend/pull/648 did not completely
fix the sample
change(https://github.com/vllm-project/vllm-ascend/issues/660) issue, I
added the relevant changes.

### Does this PR introduce _any_ user-facing change?
now, u can use following method to use mtp in deepseek v3/r1 float or
quant weights with eager mode.
```python
llm = LLM(
    model="wemaster/deepseek_mtp_main_random_bf16",
    tensor_parallel_size=2,
    speculative_config={
        "num_speculative_tokens": 1,
    },
    enforce_eager=True,
    trust_remote_code=True,
    disable_log_stats=False,
    gpu_memory_utilization=0.8,
    max_model_len=64,
)
```

or use mtp in deepseek v3/r1 float or quant weights with graph
mode（torchair）
```python
llm = LLM(
    model="wemaster/deepseek_mtp_main_random_bf16",
    tensor_parallel_size=2,
    speculative_config={
        "num_speculative_tokens": 1,
    },
    trust_remote_code=True,
    additional_config={
        'enable_graph_mode': True,
    },
    disable_log_stats=False,
    gpu_memory_utilization=0.8,
    max_model_len=64,
)
```

add notes:
1. now, we support k>1, so u can set num_speculative_tokens > 1 if there
is sufficient redundant computing power;
2. MTP is not supported in V1, we will support it when vLLM does it in
https://github.com/vllm-project/vllm/issues/13500.
3. if u run MTP failed by `segmentation fault`, u can follow v0.7.3
patch https://github.com/vllm-project/vllm-ascend/pull/236 file
`vllm_ascend/patch/patch_metrics.py` method
`__npu_async_metrics_collector_init__`

### How was this patch tested?
local tested passed and test by CI

Signed-off-by: mengwei805 <mengwei25@huawei.com>

.github/workflows/vllm_ascend_test.yaml

@@ -138,13 +138,18 @@ jobs:
             speculative_tests_changed:
               - "tests/singlecard/spec_decode/**"
               - "tests/multicard/spec_decode_e2e/**"
+              - "vllm_ascend/worker/worker.py"
+              - "vllm_ascend/worker/model_runner.py"
               - "vllm_ascend/worker/multi_step_runner.py"
               - "vllm_ascend/worker/multi_step_worker.py"
-              - "vllm_ascend/patch/patch_rejection_sampler.py"
-              - "vllm_ascend/patch/patch_spec_decode_worker.py"
-              - "vllm_ascend/patch/patch_multi_step_worker.py"
+              - "vllm_ascend/worker/draft_model_runner.py"
+              - "vllm_ascend/patch/worker/patch_common/patch_metrics.py"
+              - "vllm_ascend/patch/worker/patch_common/patch_spec_decode_worker.py"
+              - "vllm_ascend/patch/worker/patch_common/patch_multi_step_worker.py"
 
       - name: Run vllm-project/vllm-ascend Speculative Decode test
+        env:
+          VLLM_USE_V1: 0
         if: steps.filter_spec_decode.outputs.speculative_tests_changed == 'true'
         run: |
           if [[ "${{ matrix.os }}" == "linux-arm64-npu-1" ]]; then