[WIP] v2

[glutanimate]

Still very much WIP, beginning of a larger rework of pytest-anki. Filing as PR to test CI early.

Incomplete list of TODOs:

• [x] Migrate and update tooling (uv, ruff, etc.)
• [x] Simplify managing different Anki env deps - closes #24
• [x] Make deps more modular - closes #25
• [x] Apply downstream fixes
• [x] Fix web debugging on Ubuntu 22.04
• [x] Fix web debugging on Ubuntu 24.04
• [x] Add support for Qt6
• [x] Check 2.1.54 CI compat with Qt5 & Qt6
• [x] Fix CI compat with Anki@Qt6 on 2.1.65, 23.12.1, 24.11
• [ ] Make Qt API fully configurable
• [ ] Reintroduce 25.02 target and check compat
• [ ] Make Selenium optional
• [ ] Restore type-checking and linting CI
• [ ] Restore Anki compatibility check
• [ ] Stretch: Explore macOS compat again
• [ ] Stretch: Automatically check against new Anki releases
• [ ] Update docs - closes #19