[BugFix] skip model executing after clearing/updating is done

[liyonghua0910]

Motivation

对于 EP 模型，清除权重后的下一次权重更新，会直接执行一次 event_loop_normal 后半段的 execute_model，而此时 weight/cache 都还没有重建，导致执行出错。

:bulb: If this PR is a Cherry Pick, the PR title needs to follow the format by adding the [Cherry-Pick] label at the very beginning and appending the original PR ID at the end. For example, [Cherry-Pick][CI] Add check trigger and logic(#5191)

:bulb: 如若此PR是Cherry Pick，PR标题需遵循格式，在最开始加上[Cherry-Pick]标签，以及最后面加上原PR ID，例如[Cherry-Pick][CI] Add check trigger and logic(#5191)

Modifications

在权重清除/更新后，让 worker 跳过后半段的执行，回到 event_loop_normal 的开头，重新读取状态信号。此项改动对于权重清除场景是必要的，对于权重更新场景也是无害的。

Usage or Command

Accuracy Tests

Checklist

• [x] 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.
• [x] Format your code, run pre-commit before commit.
• [x] Add unit tests. Please write the reason in this PR if no unit tests.
• [x] Provide accuracy results.
• [x] 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[bot]]

Thanks for your contribution!

[codecov-commenter]

Codecov Report

:x: Patch coverage is 0% with 1 line in your changes missing coverage. Please review. :warning: Please upload report for BASE (develop@d67388a). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
fastdeploy/worker/worker_process.py	0.00%	1 Missing :warning:

Additional details and impacted files

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  Hits               ?    24993           
  Misses             ?    14255           
  Partials           ?     1890           

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