Update llm-agents with built in planner example.md

[kanlanc]

Created a draft version for the issue #173

@wietsevenema , @hangfei would love your thoughts on should be added or removed to this, I added some comments on the issue directly about adding validation on the models that support the thinking config itself.

Finally, if there is an ideal number on what should be the thinking budget usually

Some things I wasn't too clear on my lack of creativity with what would be an ideal situation to demonstrate the planner capabilities.

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[kanlanc]

@wietsevenema , @hangfei , @boyangsvl

Hey guys,

Would love some direction for the above questions so I can move forward more on this