- Add !findmacro as a proper built-in command replacing the old +findmacro
  macro that called the now-removed /list-macros endpoint
- Remove dead !twitter startup call in main.js that was crashing the bot
  on every start
- Add pythonsimo integration tests: !c (calculator), !r (reverse),
  and !add/!expl/!remove (expl redis round-trip)
- Fix CI test cases that called macros via !run +macro convention,
  use !+macro instead