Quality enhancement: Immediately interrupt execution when allocate NPU memory OOM

[leo-pony]

What this PR does / why we need it?

Protect the scene where the first problem occurs. The execution should be interrupted when the video memory application fails, rather than waiting until an illegal address is accessed.
Test result:

1. Exception throws normally:

Corresponding code:

2. HBM Memory malloc test case successfully:

3. extern launcher test with sleep and weakup:

Does this PR introduce any user-facing change?

NA

How was this patch tested?

NA

• vLLM version: v0.11.0
• vLLM main: vllm-project/vllm@83f478b

[github-actions]

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[gemini-code-assist]

Code Review

This pull request improves error handling in the NPU memory allocator by throwing exceptions on allocation failures instead of just logging to stderr. This is a good change for robustness. However, I've found a few critical issues. There are a couple of string concatenations for error messages that will cause compilation errors. Additionally, and most critically, the newly thrown exceptions are not caught at the C++/Python API boundary, which will cause the Python interpreter to crash. These issues must be addressed.

[leo-pony]

After discussing with @weijinqian0 it was determined that this PR only strengthens the quality under conditions of memory OOM (Out of Memory) and does not affect the normal operation of the path. It is recommended to merge it into version v0.11.0-dev.
@weijinqian0 Could you help review this PR?