text: Title: Paste code snippet from chat UI into editor with drag and drop
  Body: ### Problem
  
  Only ways to put text from chat UI back into editor are manual copy-and-paste and "replace selection" option on message submission
  
  ### Proposed Solution
  
  Allow to paste code text / chat messages / code snippets from chat UI into editor with drag and drop. 
  
  Figma concept:
  ![image](https://github.com/jupyterlab/jupyter-ai/assets/26686070/abfc8324-5fd6-40ab-9162-1b1f4f411b35)
  
  
  