set up another topic for order info

temporary fix for table namespacing

docs: update spark example

docs: update spark example

docs: add an example notebook for spark

restructure the repo and bump to flink 1.19.1

Install Ibis v8 from PyPI rather than using GitHub

Apply coding feedback on blog post to example repo

Replace use of internal _exec_sql with raw_sql

Replace references to Ibis master branch with main