text: Title: [Feature]: Audit and Update Examples To Use `VLLM_USE_V1=1`
  Body: ### 🚀 The feature, motivation and pitch
  
  Many of the examples leverage V0 internals.
  
  We should:
  - raise `NotImplementedError` if `envs.VLLM_USE_V1` with these
  - convert them to use `V1` if we can
  
  ### Alternatives
  
  _No response_
  
  ### Additional context
  
  _No response_
  
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