as part of this:
- wire up spoilter_text in the backend so that frontend can use it
- add spoiler_text to dummy data (+ related refactoring)
- show spoilter text in the ui (+ related refactoring)
- add/update e2e tests to check spoiler text
- improve the dummy data to be generated when building the mock db
- restructure dummy data folder structure
- remove all real data from the dummy data
- update the tests to use the new dummay data, and also
- fix the incorrect 404 test
- add a test for viewing images