Change `items` to `stuff`

I may have foolishly decided to call the db, `items` and stick to that naming convention in the code. Might collide with some python stuff. IDK, IDK python. Would be good to come up with something else. Perhaps, "choms?"

No files, tests, or entry points are named. First survey the repository for references to `items` and determine the scope of the rename; a maintainer decision is needed on the replacement name before work can begin. Done means the chosen naming convention is applied consistently without breaking the database or Python code.

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