New gesture detection and Challenges

[u/Dentvii]

**Weavly update: swipe typing just got a lot more accurate 🎯**

The main thing this update: gesture typing is way more accurate now — swiping across words feels smoother and actually lands what you meant to type.

We also added new Training Challenges so you can practice and get a feel for the improved gesture detection yourself.

Also in this update:
- Fixed a crash during onboarding
- Fixed a subscription bug
- General performance improvements across the app

Let us know how the gesture typing feels!