add runtime check for server setup in UT cases

[DiweiSun]

Motivation

Currently, if the server fails to start (e.g., due to configuration errors or missing dependencies), the script continues retrying health checks until timeout. This:

• Wastes time in CI/CD pipelines
• Delays feedback during development
• Masks root causes by showing timeout errors instead of actual startup failures

Modifications

Modify the server health check script to fail immediately if the server process crashes during startup, rather than waiting for the full timeout period.

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
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