I can’t figure out how to do this in Writer. Is it even possible?
To the best of my knowledge this is not possible due to specifications. I made a test and tried to copy a numbered and bulleted list into a text box. The numbers and bullets disappeared.
Please have a look in the Writer Guide to see what is written there about Text Boxes. You find the guide here: http://www.libreoffice.org/get-help/documentation/