[BugFix] fix dp sheduler bug in ep4tp1 when start by using multi_api_server

[ddchenhao66]

Motivation

使用multi_api_server时，不同dp的EngineService是独立的，各自拥有自己的dp scheduler，所以不再需要持有其他进程的通信队列

Modifications

为简化修改量，暂时仍使用multiprocessing.Queue；

1. api_server.py启动时设置各自的队列
2. dp_scheduler的队列列表只包含一个队列

Usage or Command

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!

[codecov-commenter]

Codecov Report

❌ Patch coverage is 63.63636% with 4 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (develop@ecfd088). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
fastdeploy/scheduler/dp_scheduler.py	62.50%	3 Missing ⚠️
fastdeploy/engine/expert_service.py	50.00%	1 Missing ⚠️

Additional details and impacted files

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  Coverage           ?   71.78%           
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  Hits               ?    38718           
  Misses             ?    12433           
  Partials           ?     2782           

Flag	Coverage Δ
GPU	71.78% <63.63%> (?)

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[rainyfly]

LGTM