* Try an idempotentish reaction create API
* Add tests for create API endpoint
* Try -> ReactionHandler
* Fix existing tests first
* Tests for .toggle; fix broken handle_existing
* Use the Handler
* Tweak http status for reaction create
* Use the category reader
Co-authored-by: Ridhwana <Ridhwana.Khan16@gmail.com>
Co-authored-by: Ridhwana <Ridhwana.Khan16@gmail.com>
