Polish ParallelExectuor constructor into small functions

[Aurelius84]

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Others

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Describe

Polish ParallelExectuor constructor into small functions

1. PR 背景：

ParallelExecutor执行器构造函数逻辑过于复杂，非常不利于后续其他模块复用此代码，比如动转静执行器升级PE工作。

2. PR 内容：

对ParallelExectuor构造函数进行了逻辑拆分，增强代码的可读性和可复用性。本PR为动转静升级PE的前序工作，不涉及新功能增加。

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✅ Aurelius84
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[paddle-bot-old]

Sorry to inform you that a059983's CIs have passed for more than 7 days. To prevent PR conflicts, you need to re-run all CIs manually.

[Aurelius84]

see new PR： #32191