[Misc] improve chat_with_tools example

[reidliu41]

• add tips for fist-time, the example models need to apply the access permission
• handle the first json output if got the prefix
  e.g.

[TOOL_CALLS][{"name": "get_current_weather", "arguments": {"city": "Dallas", "state": "TX", "unit": "fahrenheit"}}]
Traceback (most recent call last):
  File "/home/examples/offline_inference/chat_with_tools.py", line 134, in <module>
    tool_funtions[call['name']](**call['arguments']) for call in tool_calls
                                                                 ^^^^^^^^^^
NameError: name 'tool_calls' is not defined

• enhance the json parse handling
• add some debug messages

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[maxdebayser]

We already have the rich library in the test dependencies. Perhaps it would be better to use that to output colored text because hopefully it will detect whether stdout can handle colors or not.