[Engine] apiserver&engine exit when work failed to start

[CSWYF3634076]

Motivation

当前启动时如果worker启动失败，apiserver&engine不会退出。具体原因是会一直在while self.get_profile_block_num_signal.value[0] == 0:等待，但是因为worker已经挂了，永远拿不到

If the worker fails to start during the current startup process, the apiserver&engine will not exit. The specific reason is that it will keep waiting in the loop while self.get_profile_block_num_signal.value[0] == 0:, but since the worker has already crashed, it will never receive the signal

Modifications

增加判断worker进程是否存在

Add a check to determine whether the worker process exists

Usage or Command

no

Accuracy Tests

no

Checklist

• Add at least a tag in the PR title.
  • Tag list: [[FDConfig],[APIServer],[Engine], [Scheduler], [PD Disaggregation], [Executor], [Graph Optimization], [Speculative Decoding], [RL], [Models], [Quantization], [Loader], [OP], [KVCache], [DataProcessor], [BugFix], [Docs], [CI], [Optimization], [Feature], [Benchmark], [Others], [XPU], [HPU], [GCU], [DCU], [Iluvatar], [Metax]]
  • You can add new tags based on the PR content, but the semantics must be clear.
• Format your code, run pre-commit before commit.
• Add unit tests. Please write the reason in this PR if no unit tests.
• Provide accuracy results.
• If the current PR is submitting to the release branch, make sure the PR has been submitted to the develop branch, then cherry-pick it to the release branch with the [Cherry-Pick] PR tag.

[paddle-bot]

Thanks for your contribution!

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (develop@6563b83). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
fastdeploy/engine/common_engine.py	0.00%	1 Missing and 2 partials ⚠️
fastdeploy/engine/engine.py	0.00%	1 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             develop    #6322   +/-   ##
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  Coverage           ?   66.62%           
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  Files              ?      385           
  Lines              ?    51228           
  Branches           ?     7991           
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  Hits               ?    34131           
  Misses             ?    14642           
  Partials           ?     2455           

Flag	Coverage Δ
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