Support run-checkpoint in Python CLI

[linmx0130]

Addressed the bugs in devin's original code. Now Python cli supports to run a local checkpoint.

$ uv run liquidai model run-checkpoint --path ~/test_checkpoint/
Model 'lfm-3b-e-checkpoint' started successfully
Please wait 1-2 minutes for the model to load before making API calls

$ uv run liquidai stack test 
Testing API call to get available models...
{'data': [{'id': 'lfm-3b-e-checkpoint', 'status': 'running'}]}

Testing model call...
Testing model: lfm-3b-e-checkpoint
{'id': 'chatcmpl-0e8778b43eef4a3da54b42c79f743995', 'choices': [{'finish_reason': 'stop', 'index': 0, 'message': {'content': 'Silver melts at approximately 961.78 degrees Celsius (1763.20 degrees Fahrenheit). This is a key property of the metal, which is used in various applications due to its high melting point and thermal conductivity.', 'role': 'assistant', 'tool_calls': []}}], 'created': 1745444813, 'model': 'lfm-3b-e-checkpoint', 'object': 'chat.completion', 'usage': {'completion_tokens': 50, 'prompt_tokens': 43, 'total_tokens': 93}}

This PR also brings back the docker health check command, which allows docker ps to recognize the health status of the model containers.