[Misc] Fix error log for the diffusion stage timeout

[SamitHuang]

PLEASE FILL IN THE PR DESCRIPTION HERE ENSURING ALL CHECKLIST ITEMS (AT THE BOTTOM) HAVE BEEN CONSIDERED.

Purpose

Currently, we usually get these error log when running a new diffusion model, due to the model downloading time > stage init timeout.

WARNING 01-23 02:09:33 [omni.py:326] [Orchestrator] Initialization timeout: 0/1 stages ready. Missing stages: [0]
ERROR 01-23 02:09:33 [omni.py:340] [Orchestrator] Stage initialization failed. Troubleshooting Steps:
ERROR 01-23 02:09:33 [omni.py:340]   1) Verify GPU/device assignment in config (runtime.devices) is correct.
ERROR 01-23 02:09:33 [omni.py:340]   2) Check GPU/host memory availability; reduce model or batch size if needed.
ERROR 01-23 02:09:33 [omni.py:340]   3) Check model weights path and network reachability (if loading remotely).
ERROR 01-23 02:09:33 [omni.py:340]   4) Increase initialization wait time (stage_init_timeout or call-site timeout).

However, it doesn't affect the final success generation.

INFO 01-23 02:30:36 [omni.py:816]  'e2e_total_time_ms': 1263149.7077941895,
INFO 01-23 02:30:36 [omni.py:816]  'e2e_sum_time_ms': 1263148.5142707825,
INFO 01-23 02:30:36 [omni.py:816]  'e2e_total_tokens': 0,
INFO 01-23 02:30:36 [omni.py:816]  'e2e_avg_time_per_request_ms': 1263148.5142707825,
INFO 01-23 02:30:36 [omni.py:816]  'e2e_avg_tokens_per_s': 0.0,
INFO 01-23 02:30:36 [omni.py:816]  'wall_time_ms': 1263149.7077941895,
INFO 01-23 02:30:36 [omni.py:816]  'final_stage_id': {'0_47432604-f7dd-46b9-b6db-d718915e4a62': 0},
INFO 01-23 02:30:36 [omni.py:816]  'stages': [{'stage_id': 0,
INFO 01-23 02:30:36 [omni.py:816]              'requests': 1,
INFO 01-23 02:30:36 [omni.py:816]              'tokens': 0,
INFO 01-23 02:30:36 [omni.py:816]              'total_time_ms': 1263149.003982544,
INFO 01-23 02:30:36 [omni.py:816]              'avg_time_per_request_ms': 1263149.003982544,
INFO 01-23 02:30:36 [omni.py:816]              'avg_tokens_per_s': 0.0}],
INFO 01-23 02:30:36 [omni.py:816]  'transfers': []}
Adding requests:   0%|                                                                                                                                             | 0/1 [21:03<?, ?it/s]
Saved generated video to i2v_output.mp4
[Stage-0] INFO 01-23 02:30:47 [omni_stage.py:722] Received shutdown signal
[Stage-0] INFO 01-23 02:30:47 [gpu_diffusion_worker.py:315] Worker 0: Received shutdown message
[Stage-0] INFO 01-23 02:30:47 [gpu_diffusion_worker.py:336] event loop terminated.
[Stage-0] INFO 01-23 02:30:47 [gpu_diffusion_worker.py:364] Worker 0: Shutdown complete.

This PR change the init fail error message to timeout warning to avoid confusion.

Test Plan

Test Result

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• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
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