[PD Disaggregation] [Refine] Refine splitwise deployment

[juncaipeng]

Motivation

将优化PD分离模块的部分代码，从PR(https://github.com/PaddlePaddle/FastDeploy/pull/5027/files)进行拆分。

Modifications

• resourcemanager 中 pd 请求的处理接口
• splitwiseconnector 中 pd信息的处理接口
• launch 的参数
• examples示例

Usage or Command

没有改变

Accuracy Tests

参考单侧和示例

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!

[Copilot]

Pull Request Overview

This PR refines the splitwise deployment feature as part of PD (Paddle) disaggregation work. The changes split a larger PR (#5027) and optimize interfaces for PD-related modules.

主要改动：

• 重构 splitwise_connector.py 中的缓存信息发送逻辑，将 send_cache_infos 拆分为 send_cache_info_to_messager 和 send_cache_info_to_prefill 两个职责更清晰的方法
• 优化 resource_manager_v1.py 中的资源管理接口，重命名 prerelease_resource 为 pre_recycle_resource，新增 has_resource_for_prefilled_req 和 add_prefilled_request 方法
• 标准化 router 模块的参数处理，引入 RouterArgs 数据类和 FlexibleArgumentParser

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
fastdeploy/splitwise/splitwise_connector.py	重构缓存信息发送逻辑，将单一方法拆分为两个职责明确的方法，分别处理发送到 messager 和 prefill 的场景
fastdeploy/engine/sched/resource_manager_v1.py	重命名资源回收方法，新增预填充请求的资源检查和添加方法，优化 P/D 分离部署的资源管理
fastdeploy/router/router.py	引入 RouterArgs 数据类标准化路由参数，重命名 start_router 为 launch_router
fastdeploy/router/launch.py	简化启动脚本，使用 RouterArgs 和 FlexibleArgumentParser 替代手动参数解析
fastdeploy/router/init.py	导出 RouterArgs 和 launch_router 供外部使用
fastdeploy/engine/engine.py	添加属性存在性检查，避免在退出时访问不存在的属性
fastdeploy/engine/common_engine.py	更新方法调用以适配 splitwise_connector 的重构，优化预填充请求的处理逻辑
examples/splitwise/utils.sh	新增通用工具函数：端口检查和健康检查
examples/splitwise/stop.sh	简化停止脚本，统一使用 pkill 命令
examples/splitwise/start_v1_tp1.sh	移除重复的 wait_for_health 函数，改用 utils.sh，添加端口冲突检查
examples/splitwise/start_v0_tp1.sh	同上，提升脚本复用性和健壮性
examples/splitwise/start_mixed.sh	同上，保持示例脚本的一致性
examples/splitwise/start_v1_tp2.sh	删除文件，可能合并到其他示例中
examples/splitwise/start_v0_tp2.sh	删除文件，可能合并到其他示例中
examples/splitwise/README.md	新增示例文档，说明环境准备、构建安装和运行方式