Improve developer experience

[mariansam]

Working with the project during NSWI166 wasn't as comfortable as it could've been. This PR tries to improve the developer experience in the parts of the codebase students interact with the most, that being the fastcompare's algorithms and data loading.

This is now ready to merge and should be a significant improvement for future students. Multiple tasks are still on the todo list, but they're not blockers.

Tasks

• Fix all errors and warnings shown in the code editor
  • basedpyright now reports no errors in fastcompare/algo/
• Add docstrings for most functions
  • docstrings have been added where needed
• Fix defaults
  • EASE l2 now defaults to 500
• Improve initial setup
  • ? Migrate to uv instead of old Python mess
  • ? Support Python 3.14 or enforce usage of Python 3.13
  • ? Script to load datasets (CSVs + images)
• ? Fix image loading / switch from cinemagoer to imdbinfo or cinemagoerng / get a better static image set
• Improve web design
  • Show title, year and genres next to cover image
• Improve documentation / tutorial
  • Explain differences between item_id and item_idx (and maybe others) and what's used where