[Bug Fix] Proxy param & health check subprocess

[Bounty-hunter]

Purpose

1. add param check for Proxy
2. fix engine core health check

Test Plan

1. param check

Test Result

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[github-actions]

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[gemini-code-assist]

Code Review

This pull request addresses a bug fix related to proxy parameters and enhances the health check subprocess. The changes include adding a FailureResponse to the disaggregated protocol, implementing health checks for the engine, and improving error handling during generation. Additionally, input validation and request ID handling have been improved in the proxy.py file.

[github-actions]

This pull request has been automatically marked as stale because it has not had any activity within 90 days. It will be automatically closed if no further activity occurs within 30 days. Leave a comment if you feel this pull request should remain open. Thank you!