[Cherry-Pick] [RL] provide options for whether shutdown comm group after weights cleared (#5663)

[liyonghua0910]

Motivation

提供一个参数开关 --shutdown-comm-group-if-worker-idle 用于控制权重清除后是否要同时关闭通信组，启用该参数时，清除权重后会关闭通信组。如果不手动启用/禁用，则对非 EP 模式启用。

💡 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)

💡 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

Usage or Command

• 启用：--shutdown-comm-group-if-worker-idle
• 禁用：--no-shutdown-comm-group-if-worker-idle

Accuracy Tests

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!

[yuanlehome]

是不是不需要在这里添加配置，在worker_process设置一个成员变量就可以了

[codecov-commenter]

Codecov Report

❌ Patch coverage is 53.33333% with 7 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (release/2.4@dd0014b). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
fastdeploy/worker/worker_process.py	20.00%	4 Missing ⚠️
fastdeploy/worker/gpu_model_runner.py	0.00%	2 Missing ⚠️
fastdeploy/rl/dynamic_weight_manager.py	50.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff               @@
##             release/2.4    #5664   +/-   ##
==============================================
  Coverage               ?   58.96%           
==============================================
  Files                  ?      327           
  Lines                  ?    40767           
  Branches               ?     6201           
==============================================
  Hits                   ?    24037           
  Misses                 ?    14857           
  Partials               ?     1873           

Flag	Coverage Δ
GPU	58.96% <53.33%> (?)

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