Precision synchronization issue fix

[DreamerLeader]

What this PR does / why we need it?

Does this PR introduce any user-facing change?

How was this patch tested?

• vLLM version: v0.11.0
• vLLM main: vllm-project/vllm@2918c1b

[github-actions]

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[gemini-code-assist]

Code Review

This pull request aims to fix a precision synchronization issue. My review focuses on improving code efficiency and readability. I've identified a duplicated loop in mooncake_engine.py that impacts performance and suggested a refactoring. Additionally, I've pointed out a small simplification in mooncake_store_connector_v1.py to improve code clarity.

[gemini-code-assist]

This block of code can be simplified to a single line for better readability and conciseness, which is a standard Python practice.

Suggested change

	skip_save = False
	if num_computed_token >= len(request.prompt_token_ids):
	skip_save = True
	skip_save = num_computed_token >= len(request.prompt_token_ids)

[LCAIZJ]

You probably need to delete torch.npu.current_stream().synchronize() from the https://github.com/vllm-project/vllm-ascend/blob/main/vllm_ascend/distributed/mooncake/kv_transfer.py file, right? Also, is there any difference between torch.npu.current_stream().synchronize() and torch.npu.synchronize()?